It's got some interesting personalization features. The News widget in Sidebar personalizes the news you see based on your reading behavior. From the "About" for the News widget:
View news that is personalized based on the articles you read. For example, if you read lots of sports news, you'll see more sports articles. If you read technology news less often, you'll see fewer of those articles.It sound like this is subject-based personalization (e.g. showing more sports news if you read sports news), not the fine-grained personalization of Findory.
So, for example, reading a BusinessWeek article on innovation in Silicon Valley versus India in the news section of Google Sidebar changed the featured headlines to show me a few top business stories (I got an article on Vioxx lawsuits). Reading the same article on Findory surfaced articles on IBM outsourcing to Russia and China, innovation at Motorola, and growth of the startup Akimbo. Findory is more focused, more fine-grained, and more interesting.
If Google is just using subject classifications for the personalization, that might make it similar to the recommended stories at MSNBC and MSN Newsbot. Nevertheless, I am sure this will get more sophisticated with time. With both Google and Microsoft taking steps toward personalized news, this area is likely to heat up fast.
There's other personalization in the Sidebar. For example, the feed reader (called "Web Clips") automatically adds the feeds for the weblogs you visit and shows you a combined view of all your feeds.
This makes it easy to set up and configure this feed reader since, well, it requires no set up or configuration at all. It learns what feeds you might like from your behavior and does all the work for you. Very nice.
The stock quotes also learn from your actions. If you search for "GOOG" on Google and then click on the quote link in the search results, a quote for GOOG will be added to the Stocks widget in Sidebar and constantly update.
The weather came up as Seattle, WA for me automatically. Not clear if this was from geolocation (using my IP address) or from a zip code I entered somewhere at some point.
The Quick View section learns what websites you visit frequently and provides links to them, essentially automatically creating bookmarks for you.
In all, an impressive effort, full of easy-to-use, convenient personalization features. It is a strong move toward personalization from Google and an aggressive attempt to get a constant Google presence on the desktop.
See also reviews from Gary Price and Nathan Weinberg.
Update: After using Google Desktop Sidebar for a few hours, I'm loving it. Definitely worth trying if you haven't already. I gotta say, I wish My Google worked more like this.
Update: In an AFP article, Google's Marissa Mayer says, "Google Desktop is a new, easier way to get information -- even without searching. You can think of it as a personal web assistant that learns about your habits and interests to identify and present web pages, news stories, and photos that it thinks you will be interested in."
Exactly right, Marissa. Personalization complements search. Search helps you find things when you know what you want. Personalization helps when you don't know what's out there. Personalization helps surface interesting things you didn't even know existed.
Update: In another article, Nikhil Bhatla at Google has a good quote about the Google Desktop Sidebar: "We've built a platform that lets people sit back and watch the Web come to them. Sidebar is automatically personalized based on what you do on the computer ... We wanted to make it work well for all types of people, both novices and advanced users. Novices won't go in and configure the Sidebar, so automatic personalization was important for them."