If you use Google groups, you might have noticed the switch to the new version. It is a little more colorful, using html5 and integrating into the other Google properties.

Google Groups is Google’s answer to message boards. Just like with Yahoo! groups, you can create a new group and invite friends to it. They can then read the messages, or interact (depending on how you have the group set up). For example, Todd uses groups to message subscribers of Geek News Central podcast.
Switching is not that difficult. Just choose to use the new Google Groups interface, then (when comfortable) select the button on top called “Switch to the new Google Groups”.
It’s got an email feel to this new version. The left pane is the groups you are in. When you select a group, the list of messages show up on the right. At the top, you are asked to adjust your profile – either update your name or attach this group to your Google profile. Then you can message away!
Does it change the email version?
So you don’t go to this interface. You end up emailling to [whatever]@googlegroups.com. You get emails and respond that way.
So far, nothing has changed there. You can still email to google groups and get messages either when they come out, on a daily digest or never.