Im only 2 hours in to it. So far its really fun. Story is killer and they tie in a lot with the books which is awesome. Some of shepards dialog seems like he is too much of a pansy and is always going "its glad to have you back" over and over again. The combat is way better with much more unique enemies thats for damn sure. It is way faster too, which im not too sure if i like it or not being faster. Customization has improved immensely from ME2. It mixes a lot of the goods from ME1 and ME2 without breaking it however it still doesn't feel like ME1 to me. ME1 had the most bad ass enemy and everything felt fresh.
Overall i give it a 8.5/10
If anything get the art book to be honest its the best thing in the whole package imo.