If there already is a well functioning chat channel, then there is no need for another one to be created here.
Rather the opposite: many of us on #arduino@freenode.net have been pushing for the integration of the channel with the rest of the arduino community, and to become "official". You can read more here:
http://pastebin.com/ydHQdTks (an open letter written by the channel, and in the topic). Unfortunately, we've yet to have a definitive response.
For everyone:
I know that some people on the forum, such as yotson, have brought up this topic before.
The channel itself is rather friendly, and we are fairly relaxed about topic, and as a result, we are also able to answer on a wide range of topics, as there is always someone we know who has experience or an interest in that field. Also, because of the immediate nature, we can often solve issues in a matter of seconds. (For example, I've just helped mirror the IDE for someone who couldn't reach the main release through the site).
Long story short - come visit us, and if you like us, please stay and support us!
</shameless plug>