Opera 8 - Later -

Goods:
Skin change show instantly. And there is some choice already.
Fast Rewind and Fast Forward buttons, which go to the more likely previous or next page. We'll see.
Mouse gestures. Well, if you use it.
Voice control. Forward... Forward... Sorry mate, 'was talking to my browser.
Subwindows. Tabs are real internal windows, as in word you can tile your documents, you can tile your webpages. Firefox can't do that. And it seems usefull.
Typing directly in the adress bar triggers a google lucky search - sometimes. Firefox do that - sometimes.
Buttons and text fields have slightly round corners, good looking.

Bads:
The menu bar (File/Edit/View/.../Help) is not considered as a toolbar. Thus you can't place the adress bar up there.
Unfortunatly, this is my favorite layout with Firefox, having a toolbar with menu, few button, adress field, and below that the page tabs.
Then you can't have less than two toolbars (url and tabs), no minimalist AND usable layout then. Except using minimalist skins, such as Breeze Simplified MICRO V4.15.
Popup blocking is quite agressive, even in 'block unwanted' mode, blocking wanted popups.
No extensions, meaning I don't have my stumble upon button. Can't remember if extensions are considered a security breach and won't be allowed, or if it's work in progress. As there is no info on extensions on opera's features page, I suppose this is a no go.
Ads. Opera is now ad-free, good. But you don't have ad blocking functions such as adblock, ads are everywhere again.

Neither good nor bad:
Is it faster ? Well, that's not obvious. Not slower as far as I can notice.
You can call back closed windows. In fact closed windows are moved to a trash, you can then call them back from the trash until you empty the trash. Any use ?

All in All:
Clean and simple. No extensions means no fancy tweaks, it's all about browsing.
I like it. I might stick to firefox for adblock, but I really like it's style.

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