> This is exactly how I'm using Firefox, right now -- 273 tabs open. It's sitting at ~5% of CPU and 450MB of RAM. And switching tabs is instantaneous.

Marvellous. By the time I get to maybe 70-90 open tabs Firefox will consume 4-6 GB RAM and constantly hog a CPU core.

Some pages with JS cause the usual instant entire-browser lock-up.

And I admit I miss the days when Opera 10 was still an up to date browser. I don't think I ever had a (subjectively) faster browser.