In February 12, 2001, Google also swallowed Deja, calling it Google Groups (http://groups.google.com/).
Deja was a fine service, but then they started becoming less and less usable by adding more and more ads - and they also tried to be some sort of "precision buying" site. People didn't like them anymore that much. They ended up in financial trouble. Then, eBay's half.com bought the precision buying part and Google bought the Usenet archives.
Google Groups is sort of like the original DejaNews - it has a very clean interface, just like the rest of Google. They also made a Great Cultural Act by putting the old DejaNews Usenet archives (since 1995) back online (Deja took most of them offline).
In December 11, 2001, they made the entire Usenet news archive since 1981 available! This event was a Great Cultural Act in Totally Massive Scale. =)
This is, of course, only one reason why Google is my second-most-favorite web service after E2... As mentioned in other writeups, Google web search is very, very good, and their site is very light. Also, Mozilla supports Google toolbar search "out of box", and they have a gigantic search toolbar toy for MSIE, too (imitation of which is in works for Mozilla).
For Mozilla users: The toolbar search is pretty good, but I rather use the bookmark feature. Basically, I added a bookmark with URL http://www.google.gon/search?q=%s and put "g" in the Keyword. This way, I can search for things by typing "g searchterms" in the toolbar...
Why this? Well, I also added a bookmark http://www.everything2.com/?node=%s with keyword "e2", and added similar bookmarks for dictionary.com, IMDb and others. I can search from my favorite websites easily =)