The account was started by one Alon Nir, who’s from Tel Aviv. He told Reuters that he hopes the account would be “beneficial to people all over the world.” A little high minded, sure, but there’s no harm in that, I don’t think. (Unless there’s some rule in Judaism that prevents talking to God via Twitter.)
I’m looking at the account right now, and it has some 3,200 followers.
Of course, all prayers are private. Then again, I seem to remember a situation when supposedly private tweets were accidentally made public. So pray at your own risk, I guess.