I have been playing the match up game to much success in fantasy this year. There are good defenses every week on waivers that have a solid match up. Also on your waivers if Atlanta or Zona's D are out there you should grab them. I don't think I have ever seen a d for d trade.
As others have said though you aren't gaining much on the throw ins of floyd or holmes.
How about this trade I have offered:
Giving Mendenhall and Donald Brown
Getting Spiller
I have Mike Wallace on my team and would prefer not to have 2 steelers starting.
my rbs: forte, bradshaw, sproles, mendenhall, brown, tashard choice (waiver this week if fjax and spiller can't play)
my wrs: wallace, steve smith (car), calvin johnson, boldin
it's a 2 wr, 2rb, flex ppr league