2. Being a standard open protocol makes IRC better than any alternative anyway. Can you use Hipchat on a graphing calculator? You can use IRC on one.
Though I love IRC, I do wish it has some features present in things like Hipchat.
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Whether you market it as "IRC++" (like Grove), or "HipChat with IRC support", is another question, but I'd love a service that had a great IRC (and maybe XMPP) interface, plus all of those features.
The CTCP portion of IRC makes it possible to do just about anything you want, as long as both parties are using clients that support the action.
TRC offers persistence via ZNC. Some of the other points are offered by some clients.
File sharing is a work in progress for TRC, but a very important feature to me.
Inline media, file uploading/sharing, mobile messaging, persistence, log searching, APIs, etc, etc can all be achieved with IRC and is actively being developed with the kiwiirc.com client that this startup is using giving it a great start.
http://trash.io/room/whatever_you_want to make a new room
realtime, drag and drop images, youtube, vimeo and multiplayer html5 games.
ws, redis, on top of a rails app on heroku.
enjoy.