Anyway, the game has the appearance of an original, quality product. It is still in development, but it already has two playable and two non-playable factions, three tilesets, a random map generator, and a bunch of features not found in Warcraft II (such as units getting experience etc.).
Wyrmsun runs on the Stratagus engine, which is an open source engine recreation of Warcraft II.
Here's a gameplay video of the single-player campaign mode:
http://www.youtube.com/watch?v=rtVORQkWBzw
And yeah, the music in the game is from The Battle for Wesnoth

[Edit] Some discussion of the game's art can be found here.