I think it is a bias issue in regards to the deprecation, Obama's supposed flaws are his :
arrogance, professorial nature, naviete, the teleprompter, etc.

He made fun of the teleprompter bit x2 , the airplane snafu, press adoration, meeting with captain hook, building a library tribute to his first 100 days etc.

I think a lot of it just has to do with taste and bias.

Which of the last presidents has been humble in the 20th-21th Century?

The only three I can think of are Truman, Ford and Carter, the latter two of which were both horrible presidents but seemed quite humble.

His comic timing has improved (it was pretty lousy during that event in the campaign where he and McCain both did a schtick.) He seems to have worked it out though and as a head to head comparison here I didn't find Bush's timing to be much better. When Bush does comedy like this though, I have to say I'm reminded of Johnny Carson- it's not that edgy but he seems to be having a lot of fun and to me that's infectious (generally I prefer that kind of humor to 'edgy' stuff, though a few people do edgy well.)

Bush relies on a kind of silent smirking to let jokes gently settle on the audience, but the material is weak ba-dum-dum stuff. If you are not especially well disposed to Bush, you will find that really off-putting. I didn't think any of the material was strong either, though that's probably not his fault. The only thing well suited to him was showing Jeb's baby picture, which he did well. Of course, the joke that somehow he was “mad” at his brother about the recount seems totally weird. Maybe you have to be a righty or something to understand that.

Two opposite types of people are in the room, so it's the end of the world–my dog is named spot, aren't I creative… maybe not his fault. There's nothing the least bit edgy or funny there.

I guess, it's all in the eye of the beholder. I found Obama's performance so much more genuine and lighthearted than any of Bush's performances. But, again, that's just my opinion.

Anyway, with respect to what have been called “inappropriate” comments, especially the one (not by Obama) on Limbaugh being the 20th hijacker and dying of kidney failure, of course they were definitely inapproriate.

But looking back at some of Bush's inappropriate performances, CorHart just stole my thunder.

Bu let me say it anyway.

I will never forget, nor forgive, Bush's atrocious so-called joke on “looking for WMDs under his desk, here, there, everywhere—no WMD's here, no WMDs there..” while as CorHart says thousands of our finest had already died, and are still dying, for that lie.

Unforgivable!

He was a monster made more monstrous by his blistering ignorance of that fact.