Rock Band 2 goes on sale this Sunday. As you know by now, RB2 features plenty of new bells and whistles.But it also includes blasts from the past. As previously announced, owners (or renters) or the original Rock Band can export 55 of the tracks to Rock Band 2. But how exactly does this work and how do these songs display in Rock Band 2? IGN had a chance to scope this out in advance and it is pretty damn cool.