Instead of having to click the submit message button (or pressing tab and enter to navigate to it with the keyboard) have pressing enter submit the message and enter+shift to enter a new line.

When somebody say a user's name that line should stand out, for example by making the background red.

for example, if I say:
[ido]: how are you doing Julien?

Julien will see that line with a red background.

In case of a typo a user should be able to edit their last message (maybe only within the next few seconds).

The message stanzas in chat.js appear to be including the entire text of the javascript getUniqueId function instead of the output. Looks like it's just missing ().

http://gist.github.com/141073