Facebook today announced changes to the messaging centre to little fanfare, but the changes should be welcome to users frustrated with the way the service worked.
There aren't any brand new features in tow, this is more of a visual refresh. Conversations are now viewed side-by-side with other threads, so you can easily go from one conversation to another without leaving the page. According to Facebook, in the only information they give about the upgrade, "you can bring conversations to life with multiple photos and emoticons."
They also point out that search has been revamped and you can search for a senders name from the messages view, and that the service now supports keyboard short-cuts (and you can get a whole list of shortcuts inside the messaging service by hitting Alt + Q).
Not much more information is known about the upgrade yet, but according to the product page, we should all be seeing the upgrade sometime today.