1. There has been an alternative client to IWNet, in order to fix many problems the regular version of MW2's Steam/IWNet matchmaking had like: No mods, long waiting times for games, etc
This program got shut down, because of support of piracy.
2. Now, a successor of this program is to be released, but this time, it will only work with a legit copy of MW2.
If that's correct, then kudos! I owned MW2 since the beginning, played it a lot, but now, the extremely long waiting time for a game is too much to bear. I really hope this project is successfull.