Quoting PossiblyImpossible,
It seems like most RTS now all try to do something interesting or different, most often by simplifying / dumbing down the game and making it more action-packed and flashy to try and draw in the FPS crowd. SC2 is sticking to what made the original so great, while adding plenty of new content and improving on the few things that weren't so great about the original. Considering that SC was arguably (and widely regarded as) the best RTS ever, I don't see how SC2 couldn't be great.
So yes, in a simple way, SC2 will be like SC with better graphics and new units, but that description overlooks the little details and the context that makes that so exciting.
There's a problem from my point of view: While Starcraft was propably the best adaption of the RTS genre for the mass market at it's time... the simple truth is that it isn't 1998 anymore. 1998 still was the sort of the "stoneage" of the RTS genre with little competition on the horizon. We are way past that point.
Maybe it's just me... but after playing more recent games like Supreme Commander with all it's strategic options and depth, the notion of a traditional Starcraftish game just seems to be so shallow and one-dimensional in comparison. Supcom against decent opponents plays almost like an elaborate game of more complex multidimensional chess... I played my share of Starcraft back in the day... , but seriously... it's not 1998 anymore. 
The genre has moved on that's the simple truth and while there has been a lot of crap games over the years there have been real gems that pushed the genre forward as well. SC2 being a reimagining of the original starcraft however, will simply make it an outdated relic gameplaywise. With the hype and marketing budget Blizzard is pushing nowadays and the following of people in Korea worshipping them like Demigods i don't doubt it will sell anyways... which is kinda shame, because that will most likely spawn a new wave of clones with even shallower gameplay, which is really the last thing that the genre needs at this time.
And don't tell me you don't realize that, if Demigod, as it is right now, exact same gameplay and game, would be released with a Blizzard Logo tacked on..., then there would be millions of fanbois singing in choir, praising it like the second coming, and bashing anyone who even remotely thinks of criticism.
Kinda silly... almost as silly as bashing people for the attempt of starting up a community 