The original game was fun, but only to a point. Many other RTS games have taken the concept much farther and have been way more fun. Frankly, I haven't seen anything from the countless 'update' videos and 'walkthroughs' of the classes that shows me the next Starcraft will do anything different. In fact, it looks like they're flaunting the fact that Starcraft 2 will be more of the same, just with new units added and 'multi-layered terrain'.
I don't really find much improvement in mechanics that even SNES and PSX games could surpass in terms of variety and complexity. No matter how big the fanbase may be or how polished the graphics will turn out. Not to mention there's already been a number of other more recent RTS games that have been just as good looking and still managed to innovate the RTS genre. Company of Heroes and Age of Empires III come to mind.
Six upcoming games you should look into:
