I get my notifications on gmail, but I only get announcement from LJ and one of my friends, usually all comments. But I haven't figured out how to get notifications from all of my friends consistently - not sure how the setting defaulted as I haven't altered them. So, I don't know that LJ and Gmail are all that friendly.

I will say this given the data-mining google does, and the threat of a microsoft-yahoo merger - having accounts in both places is a hedge against future corporate weirdness if one must choose as it were. I have both.