Its good that you are interested in using better technologies to increase server performance but i would say at this point of time and with this level of traffic, it will be a timewaste to go into those. Rather work on increasing the performance by code. Those kinda optimizations, for me, kick in when we are talking more than 100,000 views in a day. Just a suggestion
Oops .My bad. Maybe I didn't explain myself clear enough. What I meant by hundred was referring to "registered users" browsing my forum at the same time.
Currently I'm running two different forum on two different server. One with APC installed another one without it. What I can see from the result was that a big different on the server load. Another reason I run it was pages load snappy, as if they are run from localhost.
The above two points are the main two reasons why I run it.
Anyway, I'm interested to hear beside APC, is there any other tricks to increase your server performance?