Call me a loudmouth, but I find it extremely annoying we can only type so few characters per message. This problem is compounded by the fact that we're allowed to continue typing, but unable to send the message, and forced into edit-mode where we're left guessing how much of our thought needs to be copy/pasted into the next.
If anything, this Social UI update has made me less social. Rei makes a lot of good points, too.
That, indeed, is very annoying, but if they do now use IRC server for the chat, as it would appear very much (has it been confirmed for real yet? It may not be IRC based even though it seems very, very similar).
So we know that client can send, by default on IRC servers 500-len(target) bytes of text, but only (498-len(target)-len(senders_ident+host)) gets through, and i just tested, i was only able to send 150 characters (unicode?), still seems rather low number... then again, don't know how they define user's ident (nick most probably) and host (IP maybe) and the target (channel, could be in fact something like "Chat_Society_#societyname" or what ever internally.
Someone could go try all kinds of combinations out and figure out the length of different variables
And back to the main point, yes, they should atleast inform when you can't send anymore characters, and the lines are way too short (maybe limited by the game/server though, for spam reasons, but this imho could be removed in soc chat and private chat).
There's always ignore now
Edit: Just tried on a custom channel and was again capped at 150 characters, so, guess there is a cap
And could only send 129 characters in private message to myself.