Is not a disappointment. Actually, a very nice game to end the millenium with.
Tomba's girlfriend Tabby has been kidnapped by Evil Pigs, and it's up to you to stop them. Like the prequel, its an unusual hybrid of two genres. There are also 130+ little subquests to perform. While the game looks less 2D than the original, the game still works in a 2D fashion. You travel along a path until you reach an intersection, where you can then pick one of several directions to continue in. So it really isn't 3D, but gives a nice illusion of it.
There's a number of improvements from the original. The world is easier to traverse, the items in the subscreen are more interesting, and the 3D engine looks great. Also the various suits allow for different abilities and most of them are interesting to use. You should be able to complete this without much trouble, though some puzzles are pretty difficult.
Tomba 2 is one of the best looking PS1 games. The models are nicely done, and the world springs to life with color and animation. Also the music's been reworked from the Japanese version. The voiceovers are surprisingly not bad, and work pretty well in the game's favor.
Its a nice treat for fans of the original.