It was a good game, don't get me wrong, but I felt underwhelmed. I actually thought the storytelling itself was pretty awful. The love story seems really forced and cliche, I don't remember any of that from the original Starcraft. Then there is that random scene where Kerri goes apeshit on Zeratool for no reason (she hasn't even met him when she was human, and now she has amnesia from her time as Queen of Blades, remember?). And that's just a small sample, I felt the storytelling was quite forced/cliche/trite.
On the other hand, I felt the graphics and design were very well done. The campaign units themselves, especially the evolved ones, are ultra overpowered (even more so than the units from WoL campaign). That in part explains why this was an easier game overall.
Also, I was disappointed that there was no secret mission. I thought all Blizzard games had a secret mission, but alas!