Wow, I missed this topic for this long? I need to get out of UGW more often.
Anyway, to an LP, you need to be able to do three things:
1. Deeply enjoy the game, unless you're a machist that enjoys pain. Xan didn't like The Dark Spire too much.
2. Have loads of free time. This was my problem as summer stuff got in the way REAL fast.
3. Be able to write a "documentary" because if it's a screenshot LP, you're going to be doing a lot of screenshots/copying text by eye and hand.
Regardless, I'd give LPing a shot, as if you enjoy it, you'll love it, if you hate it, just drop it before you get too far in. Making witty comments is optional, and your own funny characters are optional too, but liven it up a bit.
So yeah, got time and interest as well as that heart of a reporter, and you're fine.