Chris Crocker: Annoying, probably something Fe.
Boxxy: Something Alpha SF makes sense.
Nigahiga: Don't know of him, love that video though. Ne-ENXp could work.
It's Kingsley Bitch: 6-second impulse typing says INFp
JennaMarbles: She's confused me for a while. I thought EXFj at first, but she really doesn't speak in terms of discrete sentiments like Fe types tend to do. Definitely extro and Fe/Ti valuing though, not ESTp, so I landed on Ne-ENTp.
TheAmazingAtheist: Something Ti valuing. My gut says "obvious ENTp durp" but my head has a bit more trepidation.
Fred: Watched the first four seconds and had to turn it off. God damn.
iJustine: I have her down as Ne-ENTp for the same reason as JennaMarbles. Also she reminds me a fuckton of a (male) Ne-ENTp friend of mine.
While we're at it:
Toby Turner: Ne-ENFp 7w6 sx/so
CopperCab: some extrovert, perhaps ESTp. Love to see what other people think
KevJumba: Non-ENTp Ne/Si irrational???