Burning Out On Modern Warfare 2, Take 2

After getting a second wind on the game a couple weeks ago, I'm now starting to tire of it again. I managed to level all the way up to 70, but so far have declined the offer to go into "Prestige Mode" where you start all over again back at level 1. I spent several hours today trying out the level 70 gun - an AK47 - and now have gotten enough kills with to equip it with a heartbeat sensor (my 3rd such gun I've brought to that point, along with the SCAR-H and Famas). But there just doesn't seem to be a whole lot of point to continuing, especially since we haven't had any new maps yet to break up the monotony. I think it might be time to rejoin my Aliens Vs Predator campaign, already in progress.