First impressions on my end are very solid. It was very fun to play.
I didn't notice the clunkyness that most were complaining about, but then I was having too much fun to care.
Combat felt much more involved on my Sith Juggernaut than my melee characters in WoW. I felt like I had more control over my resources.
I didn't do much PVP, but it felt solid. Keep in mind, this is beta, they were still tweaking numbers in the last build I played in. In response to a lot of the people above, most of the "2-shot" specs/rotations have been killed over time throughout testing. I highly doubt we'll see them on live, or if we do, they will quickly be taken care of.