All sorts of celebs are weighing in on The Donald as of late ... and they have some not-so-nice things to say about The Apprentice host and potential presidential candidate.

Comedian Bill Cosby spoke to NBC about Trump's possible 2012 campaign.

"He’s full of it,” Cosby said. “You run, or shut up … but the only thing he's running is his mouth."

And Robert De Niro said Trump is like a "used car salesman" when it comes to the businessman's questioning of President Obama’s birth certificate.

Last, Jerry Seinfeld pulled out of an event benefiting St. Jude Children’s Research Hospital because Trump’s son, Eric, was hosting it.

But Trump, who's used to being the one giving the criticism a la his Apprentice franchise, doesn't take such critiques lightly.

See what fightin' words he had in response to these three -- and the bizarre statement that one celebrity gave in support of Donald -- after the jump!

Bret Michaels has filed suit against the Tony awards for a 2009 accident that he believes caused the nearly fatal brain hemorrhage he subsequently suffered.

Michaels, who performed the opening number of the show with his band Poison and the cast of Rock of Ages, was flattened by a piece of scenery that dropped as he was walking offstage. The Tony awards blamed Bret for "missing his mark", which at the time left Michaels with a broken nose and bruised lip.

But less than a year later, Bret was rushed to the hospital after suffering a brain hemorrhage.

In the suit filed today against the Tony Awards and CBS, Bret claims "One of the most common causes of this type of hemorrhage is head trauma -- exactly like the one Michaels suffered at the hands of the Tony Awards."

Bret is seeking unspecified damages.

Bret Michaels' heart surgery on Monday was a success, according to a spokesperson for St. Joseph's Hospital in Phoenix, Arizona. The musician/reality television star is recuperating in the intensive care unit after doctors performed a cardiac catheterization and inserted a permanent closure device in his heart to prevent the abnormal flow of blood.

"Barring any complications, I should be out within three to four days," Michaels told the Arizona Republic. "Then, I will be down for three weeks. I don't know if I can sit around for that long, but I'll try my best." Michaels' rep added, "Bret is looking forward to feeling 100 percent again."

Michaels was treated for a brain hemorrhage last April, and it was at that time that doctors discovered the hole in his heart. Without the procedure, doctors say Michaels risked developing blood clots and an additional stroke.

Bret Michaels will undergo heart surgery at St. Joseph's Hospital in Phoenix, Arizona today to repair a hole in his heart, according to his rep.

"Barring any complications, I should be out within three to four days," Michaels told the Arizona Republic. "Then, I will be down for three weeks. I don't know if I can sit around for that long, but I'll try my best." Michaels' rep added, "Bret is looking forward to feeling 100 percent again."

Michaels was treated for a brain hemorrhage last April, and it was at that time that doctors discovered the hole in his heart. Michaels will undergo a cardiac catheterization where doctors will insert a catheter into a vein in his groin, guiding wires and a closure device into his heart with cameras. The closure device will remain in Michaels' heart permanently to stop abnormal blood flow between the two chambers of the heart, which is thought to have caused the stoke he suffered last year. Without the procedure, doctors say Michaels risks developing blood clots and an additional stroke.

We'll be sending good vibes his way!

Courtesy: Bret Michaels

The 47-year-old rock star popped the question on the finale of VH1's Bret Michaels: Life As I Know It.

After a roller coaster relationship with Gibson over the last 16 years, the Poison frontman tells Us about the moment he gave her the ring. While on bended knee, he said, "Please say yes or the rejection will kill me right now." Spoken like a true rocker!

Michaels, who suffered a brain hemorrhage earlier this year, gushed about his bride-to-be telling the mag, "She's the one who put up with me all these years."

They do make a beautiful couple. Congrats Bret!

Bret Michaels, who was rumored to be the reason Miley Cyrus parents Tish and Billy Ray recently filed for divorce, flat-out denied that he had an affair with Tish this morning.

When asked if he and Tish had ever become more than just friends, Bret said, “The answer is no." He told Fox & Friends, "It started out with me and Miley simply working on a song together. Her mom, Tish, likes ‘Every Rose Has Its Thorn,’ the first concert Miley ever saw was Poison, and so they wanted to remake it for the new record." But the relationship never turned romantic.

“When I was in the studio, Miley came in and sang on my song, a song I wrote for my album ‘Custom Built,’ and she came over and sang on that and honestly, she did a beautiful job, and that was it," he said. Then they started with all the controversy.”

Billy Ray Cyrus filed for divorce from his wife Tish of 17 years last month. The couple is asking for joint custody of their three minor children.

The report of an alleged affair between Poison frontman Bret Michaels and Miley Cyrus' mom, Tish is getting shut down by the rocker's rep who made the following statement:

“This is untrue. My client is not that type of person, he has worked with Miley Cyrus and Tish on a professional level."

A source close to the Cyrus family tells X17online exclusively:

"Bret has known Tish and Billy Ray for a while now. The rumors started when Miley recorded Bret's song Every Rose Has Its Thorn. Sure, Tish has hung out with Bret, but that's it. They were just hanging out as friends. It's pretty obvious that this is a totally made up story. I honestly feel bad for Miley."

X17online videographers caught up with Miley just yesterday and she told us, "I'm sad" about the breakup. Billy Ray and Tish Cyrus are getting divorced after 16 years of marriage.

We were shocked to hear that Billy Ray Cyrus filed for divorce last week from his wife Tish of 17 years, but the reason for the breakup of Miley's parents may be even more shocking: Tish was allegedly having an affair with rocker Bret Michaels!

It all started this past February, when Miley recorded the duet, "Nothing to Lose" with the 47-year-old.

Michaels apparently became "close with the entire family," a source tells Us, but not quite as close as he did with Tish!

In fact, Tish even pushed Miley to record "Every Rose Has Its Thorn" on Can't Be Tamed! In June, Miley told Ryan Seacrest, "Every time we go to New York we have to see Mamma Mia! for like the 12th time because my mom loves it, and that's kinda how "Every Rose" came about... she made me go to Rock of Ages, too! And my mom said 'I love that song, I forgot how much I loved it' and so then I did it."

"It was a professional relationship that turned into something more," says a source of the affair. And, "Billy Ray was completely unaware of what was going on."

Both Michaels rep as well as a spokesperson for Tish deny the dalliance, but there has to be SOME reason for the sudden split. And somehow, Tish and Bret just kind of make sense, don't they?

Billy Ray is asking for joint custody of the couple's minor children, Miley, who will be 18 later this month, Braison, 16, and Noah, 10.