It blows away every 3D fighting game I've ever played (even "Virtua Fighter 3," and by a much bigger margin than I expected!), so go buy it when you get your Dreamcast, or feel like a total fool when it's sold out the next day.
The gameplay is a nice mix of intricate strategy and fast-paced action; online play is an option; and commentators John Motson and Mark Lawrenson are back, accents and all.
While the AI has a few problems, and there is an occasional rough spot, the finished product is one of the most complete and compelling games we've played, and easily the best MechWarrior game in the series.