Compare new and old Google Search side-by-side: http://tlrobinson.net/misc/googlecompare.html

Caffeine is twice as slow...

Why is the sentence about Wolfram Alpha in this article?

Ask it! :)

If any one of you get paid for journalistic writing and at any time need a pseudonym for your byline, I beg of you, use Wolfram Alpha.

Does this mean I have to change my username?

My testing: Similar results. Similar speed.

I still see the same spam I reported weeks ago in the index. The new index even shows it at #1!

Users don't, but I'll bet a lot of hackers do. Apparently it has had an effect on rankings - what you consider to be "little effect" can be huge deal to someone whose business relies heavily on referrals from Google. And the speed difference that I've experienced is actually quite noticeable.

edit: To give some concrete data, I took the queries I've done on Google today and compared the first page of results. Roughly 40% of the results were ranked differently than they were before. News results were more recent with Caffeine. Previous requests took perhaps, 1/2 a second to display - it's relatively instantaneous now.

I am wondering, however, if the display time is faster now because the new site doesn't have much user load where the old google site is relatively busy.

The claim about 'faster' is that newer search results show up sooner than they did on the old google. That is, new results get indexed for display earlier.

Hackers like me would be interested in what they have done even if it made no significant difference to the end results.

I think there main go here is trying to position them self against all the new real time search offerings.

What have you learned about what they have done that is interesting?

Well nothing but I mean it would be interesting, should they happen to go into a technical explanation.

Interestingly, stack overflow is not popular with Caffeine...

"HTTP Requests optimization": 2nd result with old Google. Not in the first 3 pages with Caffeine.

For Google's data centers: faster == cheaper. They need less servers to handle the same amount of load. Even a few % at this scale could be a big saving.

I think a reasonable answer (to a reasonable question, not sure why you're being downvoted to oblivion) to why it's newsworthy is the very fact that Google chose to announce it. Google must have made many changes to both the ranking algorithm and the responsiveness of their system over the years - I don't recall any announcements of them, codename attached (although it's conceivable I missed them somehow).

Part of the motivation may be to create some publicity to counter all the Bing/yahoo deal/etc publicity.