I'm using Google Reader on my iPhone, but I use the mobile interface. I haven't had any problems at all. My main complaint is that it would be nice if it let you set where you want to go after you mark a feed as read. Typically I do all my reading through the Tags screen and would like for it to take me back to that screen when I mark the feed as read.
I think I figured it out: There was an ampersand in my google account name. So when GR tried to load the page, it was apparently choking on the very top line that says "beej & beejwife's reading list." Something must have changed with GR, as that ampersand has always been there. Who knows, I'm just glad to have my reader back.