Always a tough question! It's a close battle between Okami (for its whimsical aesthetic, its fun basic platforming, and the good re-use of its drawing mechanic. Also its story) and Uncharted 2 (for its outstanding character relationships, story, and shiny level of polish).

Since Uncharted 2 is new on the "omgLOVE" list, I'm going to give it a year or so before I declare it as surpassing Okami as favorite.