US med schools use the rationale that performance on the MCAT is an indication of how one will perform on the USMLE when they reject someone who has low MCAT scores. I'm here to say that one does not necessarily predict the other. I ended up going to school in Mexico because of rejections by US schools. I took Step 1 last summer and did fine... better than "just passing" -- but not as well as my classmate who got a 231... So you may not get into a US school with crappy MCATs, but you can still score high enough on the USMLE to get a competitive residency.
As far as verbal -- it's definitely written to weed out non-English speakers, given that it's a timed test and you have to have a certain level of vocabulary to get through it. But there's no verbal section, per se. It's all science, which is probably what saved my butt...