I know that currently the guys over at ArenaJunkies are saying Relic of Yu'lon 2/2 and Hydra are 2 of the best trinkets for warlocks. Both have relatively high uptime with Hydra being the big one and giving a buff of nearly 2.9k int for 40 sec. While Yu'lon gives a nice static 1030 int with a ~3.3k int proc.