I don't understand how curved tabs are supposed to get "out of the way". The new design seems to use less standard UI elements to push it's own (WinXP / Fisher-Price) agenda: I don't see any gains here and I reckon they just want to appeal to the chrome crowd.
I'm surprised Emacs was not mentioned. It provides a nice cross-platform interface to ... everything. Also everything (including looks) can be customized!