QUOTE(angelfan @ Aug 12 2007, 03:01 PM)

How do you know what seats will be available at TKTS?
You can't find out what will be available, but you can get an idea- if a show comes up every day on the website, chances are it will be on sale o the day you want to go. (www.officiallondontheatre.co.uk/tkts)
QUOTE
I like to sit in the front stalls.
Then you probably ought to book ahead- I've never been sold a particularly bad day seat (actually, I have, but that was only because I was being cheap), but you do have to take what you're given, which will be the best they have available- there is no choice whatsoever with TKTS, or (as far as I'm aware) any of the discount ticket agents around Leicester Square.
Hope you have a good trip!