It’s clean – and basic. Very basic. But an interesting start from Google and nice to have your first chat in a new IM – ever! At the moment it’s only open to people with Gmail addresses, but those are so easy to get they really should just open it up to the masses now.
They also have a commitment to open standards to mark them out from MSN\Yahoo\AOL. Connectivity between different IM programs would certainly be a good thing – and Google may bring pressure on others to move in that direction. We’ll see…!