I don't have a bugzilla account yet, and since I'm at work without e-mail I can't create one right now, but I will look for a bugzilla entry.

I noticed this problem right away, since some pages I go to are set to open all of their links in a new window. Opera crashes to the desktop after a few minutes of this. I searched google and found alot of other users comment on this problem as well. I'm going to install the latest version of Minimo and see how it works.

If you have a 770 you can try it out, open your links in a new window and after about 5 minutes of that it seems to crash.
I do have popups set to only open requested popups, so I will change that to always allow and see if there is an improvement.

EDIT: If you look on google, you will see lots of referrences to either opera disappearing (aka crash to the desktop) or they will specifically say it crashes when opening a new window.
Seems to be tied to opening links in a new window, as it only crashes when the link directs to a new window.