Man! This thing is buggy! The developers sure have some work to do. :-)
I sent a couple of things to the deep black hole that is "Beta Feedback", but it wasn't very encouraging to see it go to their "customer care" system, so I'm not sure I want to do that anymore.
The bugs are tons of little things. Bad displays when data is missing. Double HTML entity encoding. Not dealing well with a changing email address. Sloppy programming. Things that you ought to catch as you type it out the first time ("what do we do if the user didn't fill in the occupation?" , "if we are forcing the user to enter a description for the blog, should it say "check your character limit!" when he doesn't enter anything?"). Etc.
And the URLs are generally not emailable. When I look at my own 360 blog it says http://blog.360.yahoo.com/blog/. "My Page" is http://360.yahoo.com/my_profile.html. Why do they make it hard?
All that being said; it does seem pretty neat. Will it end up being more useful than the other social-networking, blogging in a box, etc etc sites?