Tested marks crits against a knight.
22.5% critical hit chance in the character sheet, after buffs.
21/74 hits were critical. (28%)
Seems like a big difference, but it's a small test. Not sure if that's significant. What worries me more is that on the live servers I can get around 75% crit chance with a marksman, shooting from max range. For the majority of marksmen this will increase their critical hits, but for the ones who skilled and used their range to get crits it's quite the nerf.
crits on live servers: