Two things I noticed -

1. No tab 'recycle bin' (you can get this with extensions in other browsers, but I always liked that Opera had it out of the box.)

2. The downloader is similar to Chrome's one, and I've always hated Chome's downloader. I want my browser to ask me whether I want to open the file (i.e. save into /tmp and open) or to save. I download a lot of things such as Office documents, tarballs, torrent files (etc) that I don't want to have to manually delete from my downloads folder when I'm done.

I can appreciate that this is a beta version, but right now, it looks a lot like Chrome with a different skin. I just hope it doesn't remain like that for long, as Opera is the one browser that annoys me the least.