Facebook Chat launched on Saturday to a few select networks, in the ubiquitous 'beta' mode. So far so good, with the lucky few who've been trialling it reporting "it's a great implementation". A permanent, unhideable Chat bar appears on the bottom of every page on Facebook, which shows your various IM conversations, notifications and online contacts. Whilst the default setting for conversations is within your Facebook window, you can minimise it, or open a new tab for that chat. Status updates are also integrated into the Chat window, plus your contact's actions - so if...