This is only of interest to fellow Blogspot users out there, but I've officially made the big switch to "beta" (which I think is not really in beta status anymore). It was so simple. No problems at all, even with my custom template. Just wanted to share the knowledge. . . . I resisted, and there was no reason to worry. I think that there are a lot fewer problems with publishing etc. I'm not sure about picture uploading. That remains to be seen.
Also, for those of you who haven't switched and are having trouble commenting on those that have switched, just go ahead and set up a google account (that's an option on the comment screen). You'll have to do it anyway when you switch over. I had done that yesterday just so that I could comment, after not being able to comment for a couple of days.