Most people write their speech in advance and then, on the night, copy and paste it in bite-sized chunks into the ceremony window on IRC. It makes the ceremony run more smoothly if you do this - unless you happen to be extremely good at making up speeches on the spot!
There's no word limit but do bear in mind that you need to retain your audience's attention - an audience which is pretty hyper and probably chatting in at least two other windows while you're pasting your speech. A long speech is less likely to keep their attention.
Yvonne
