The original version of StarCraft will remain available but, impressively, will now be free. Even more startlingly, as StarCraft Remastered uses the same codebase as the original, players will be able to switch between modes at the touch of a button and original players will be able to play against those using the new version of the game in multiplayer.
More controversially, the UI will apparently not be improved. This means that you will still only be able to select 12 units at a time and you won't be able to auto-send newly-built units to resources.
Despite these age-old limitations, StarCraft is still widely regarded as one of the best real-time strategy games of all time (challenged only by Company of Heroes, Hostile Waters and Homeworld), mainly due to its sublime unit balance between three completely different sides and fast-placed gameplay. Arguably, StarCraft II added too many variables to the mix and made the game a bit more challenging, whilst the original's smaller roster still allowed for a wide mix of strategies whilst being more constrained. Less arguably, the original game has a far better-written, more interest and more concise story than the sprawling, increasingly silly sequel.
Also getting the remaster treatment is (probably, although it's not been quite 100% confirmed yet) Planescape: Torment. Widely-regarded as the greatest CRPG of all time, the game is set in the Outer Planes and the bizarre city of Sigil, and sees the player taking on the role of the Nameless One, an immortal entity who has to discover the secrets of his past and the nature of his own reality. The game is notable for its commitment to dialogue, characterisation and ideas over combat, blood and looting. The game recently gained a "spiritual successor" in the form of Torment: Tides of Numenera.
Planescape: Torment Enhanced Edition is being handled by Beamdog, who previously handled the expanded and enhanced versions of both Baldur's Gate games and the two Icewind Dale titles.