In reply to Gthorn:
There's plenty of good advice on this thread but the thing that really needs said is - it depends what it's like at the time.
It could be full Arctic storm conditions; it could be calm and mild.
You could be working hard to stave off hypothermia; you might be more worried about sunburn.
There could be deep powder, or bulletproof ice, or no frozen stuff at all.
And, of course, it can all change very quickly.
Here's Christmas Eve 2006, on Afterthought Arete and the Fiacall Ridge. Not really typical, but can still easily happen.
Pay attention to the conditions, be sensible about doing what fits them (there are loads of options) - and have fun!