Not only that, according to this: http://www.geektechnica.com/2009/12/move-over-chrome-opera-n... Opera even beats the webkit nightly in sunspider benchmark.
On windows. It makes a lot of sense to specify an OS in these cases.
I did a benchmark with Opera 10.50 alpha Chrome 4 dev and Safari 4. While the numbers not the same, Opera is still faster than Chrome and Safari. I didn't try webkit nightly because chrome dev outforms webkit nightly in my previous tests.
Thought I'd give this a try since I never gave Opera much of a chance, and I'm usually very tolerant of alpha/betas as long as they mostly work. Lasted about half an hour - Google Reader doesn't seem to work right, and GMail also stopped responding after a while.
I've had zero issues with Google Reader and GMail with all prior 9.x and 10.x releases. So maybe your experience is particular to this alpha release.
If there was some sort of adblockplus for Opera I'd jump ship from Firefox in a heartbeat.
Opera has had ad blocking built in since at least 9.x, if not earlier. It does the job for me; I don't find it wanting. You can point and shoot to block anything that happens to get through the default filters, and the filtering takes wildcards by default, even. Meaning clicking an ad will block all ads from the same domain or parent path (e.g. adserver.tld/ads/*). Shift click to block just a specific image. The common text ads are also filtered.