The only hiccup in the transition is that you may need to "convert" your eGroups ID into a Yahoo ID. You'll definitely need to do this is you own or moderate any groups. You can convert by going to http://groups.yahoo.com/convwiz. The form will require you to give more personal information than I like, but you can then edit your preferences later and delete that information.
Speaking of privacy, I recommend you check out http://sneakemail.com/. It's a very cool free anti-spam and privacy service.
The good news is that there are a few more features, the interface has been cleaned up a bit, and it's not any slower nor has anything been removed.
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