Ginny,
... can someone help me with what "liking" a message does? Other than
showing when messages are being read on a group's page, is there any
other purpose/use or are there stats somewhere ...
There is a long-standing wish-list item in beta@ referred to as the "notification overhaul". There are a lot of specific ideas wrapped up in that concept, but the gist of it is that there should be a more complete set of notifications that members can choose to receive on web or email or both. And a larger list for moderators/owners as well.
The "like" button is a specific case where notifications would be useful. Some members would like to be notified when someone like's their post. Others might like a notification when someone likes anyone's post.
On the web, the notifications could take the form of a button with a count of new (since last time you looked) notifications. Clicking the button would open up a list of these notifications. That proposed form would be a lot like the Notifications globe that appears in the logo banner on Facebook.
In email the notifications would be simple emails describing what happened and providing a link to it (where appropriate). It would probably make sense to offer choices like immediate notification (per event) versus one message per hour, or per day (i.e. notification digests).
But none of that has been nailed down in any detail. It has been a conversation with a variety of ideas presented in several topics over several months.
Bottom line: I think it would take a notification system of some sort to fulfill the hope that the Like button could become a commonly used alternative to "me too" postings.
Shal
Shal Farley