Matthew Pouliot tweeted this yesterday:
"My initial guess is that Salvador Perez misses first 3 weeks after knee surgery. Loses 50 AB and goes from $6 to $5 in AL-only."
After subtracting 50 AB from my projections, I have Perez ranked as the 24th best catcher. I have him reaching 41R, 45RBI, 7HR, 2SB, and a .280 AVG. Based on my projections, he's still the 7th most valuable catcher in the batting average category.
Considering you can DL him and pick up a replacement for the early part of the season, I see no reason to not target him if this injury is this minor. Especially since news like this should cause him to drop a few rounds (he went in the 14th round in our 16 team cafeholics n00bs league).