In _The Big Bang Theory_, Will Wheaton plays the character "Will Wheaton" but that character is an exaggerated version of Wheaton’s public characteristics, it’s not meant to be a true-to-life version of himself. The same is true for James Van Der Beek’s character in _Don’t Trust the B— in Apt 23_; though named "James Van Der Beek", we are not supposed to think that character legitimately portrays Van Der Beek’s true character.
What challenges do actors face when playing "themselves"? Research through interviews might provide insights into how the actors feel. It seems like both men are having fun with the exaggerations, but are there difficulties? Do they struggle with fans who are unable to make the distinction? Do such roles diminish an actor’s credibility by making their career into a joke, or does it create additional name recognition and re-ignite careers?
Probably a third actor/role should be added to round out this discussion.
Interesting topic! If you decide to write this topic, you need to differentiate cameos and actors actually playing themselves for a whole film. It's also worth looking at Sunset Boulevard as it is a fascinating exploration of the star system and the evolving film industry. Billy Wilder uses Buster Keaton, Gloria Swanson and Erich von Stroheim for a reason - they all play characters who are very similar to themselves and the way the film industry has treated them and forgotten them. The names change, but they are actually playing themselves and their lives on camera. Thrilling! – Rachel Elfassy Bitoun5 years ago
"This is the End" is probably the best recent example, and the stories of each of the actors getting in real fights due to false ones they wrote for the film that were too close to the truth is a fascinating story in and of itself. – smartstooge5 years ago