Tickets went on general sale on TicketMaster at 11 today. I've got a pair for the 18th - appears to be unreserved seating (looks like all the lower down reserved stuff has already gone), and for the 18th is for the whole day (other days have separate morning and evening tickets). So should have finals galore to watch.
Interesting chance to see the new Sir Chris Hoy Velodrome as well.