This year, Ramos hit 254/292/370 in 295 PA for the Twins' AAA affiliate. He hit 5 HR, 14 2Bs, and walked 12 times. Those numbers might have you doubting that he'll be productive in the bigs. However, he managed to hit 296/321/407 with 3 2Bs in a brief, 28-PA stint on the Twins earlier this season. That's too small a sample to be confident in the results, but it adds up to a 101 wRC+. League-average offense from a catcher would be fantastic. Another entry in the encouraging-but-inclusive department: Wilson has been 317/349/483 in 63 PA at Syracuse since the Nationals acquired him, with 2 2B, 3B, and 2 HR. Does he thrive under pressure? Countryman Jesus Flores hit a Nieves-like 153/275/254 in AAA in 2008 before spending half a season in the bigs and hitting a respectable 256/296/402. I think we can hope for league-average offense. Keep your fingers crossed that he can take a walk or three.
As for performance behind the plate, he allowed 4 SB and had no CS in his 63 innings in the majors so far, with 1 WP. However, he's managed 23 CS with 22 SB in 67 games at AAA this season. That's a Pudge-like 51% CS--remember that league-average is only 29%! He has 4 PB in the minors this year, which is a bit worrisome given the Nats pitching staff. Still, I think we can hope for league-average defense. Cross your fingers that he can block the balls in the dirt.
Add up a league-average defensive catcher and a league-average bat and you get 3 or so wins above replacement, about a "B-" on the Doghouse Curve. I'm excited to see that on the field for the Nats, and you should be, too.