Just wanted to add to this thread, and say I'm also having this issue as well.. If I might, I can share a few extra details which might help the developers in pin-pointing the problem;
PROBLEM: I went to the server browser, and it would report 0 number of servers on the network, but yet it would report a large total population of players across the network, I assume accurately. I did try turning off all the filters to see what would happen, and that brought up some servers (about maybe 70 or so at the time), but which were ALL empty... (even with the total population on the network at the time being reported at over 2000). And if I attempted to connect to any of those, they would not let me, stating the server had "Downloadable Content" which I did not have..
In addition, I noticed something odd which may be part of what the problem is. If you click through the tabs across the top of the browser screen so many times, the total number of servers available suddenly drops to "0" and refreshing will not do anything to fix it... you have to close down the game and wait for a while to re-run it and to get the server browser working again.. Or you can shut down the game and STEAM, and immediately re-run everything to get it back without waiting.
HISTORY: Before the current patch, the problem was only sporadic, the browser worked somewhat off and on. But after the patch, the problem seems to have become permanent.
MY SYSTEM: consists of an AMD Quad Core processor, 4 gigs of RAM, On-Board Sound, and Networking (NVIDIA chipset), and a Sparkle 9800GT Video card, running on the Windows 7 Ultimate O/S. Connected via a Netgear Router.
In other thoughts I plan to check out the network configurations, and router ports and see if any of that might matter. I'll get back to ya. I'm confident this will get fixed by release date.
CaveSquid
