This used to happen to me the day the game was released, my reason was because my internet was out-of-date.
There's 3 ways to solve your problem:
1) On your system (PS3 / PC / X-BOX 360), do an internet connection test.
2) Use an ethernet cable. (Because it's always faster than Wi-Fi)
3) If you don't want / have an ethernet cable, try bringing your router closer to your system (PS3 / PC / X-BOX 360)
If these 3 solutions don't work, then I suggest you should change / upgrade your router.
Hope this helps
Hi i have this problem aswell.Im in the UK[England] I have a PS3 i have try'd using ethernet and Wi-Fi[The router is right next to the PS3] And the only one i can join.It takes about 5-10 mins to find a TDM.I can't join CTF or anyother.Please help.It only joins me on Empty matches with no other players..Please help[I dont know how to make my own Question page, sorry]