2001 has definitely earned the right to be considered the best ever. But I reckon 2008 is a decent chance to be spoken about in the same vein (not suggesting it will be better) but at least good enough to be comparable. Have a feeling though that the 2001 midfielders will be superior (can't imagine better top end midfielders than this draft) and the 2008 talls might be a little better, but its still so early that the initial assessment could be way off. Certainly no other year after 2001 has come close.
2008 would be the closest out of other years. Still 2001 is better.
Have a look at the rookie list from 2008! (btw -Hawks and Freo did very nicely from this rookie draft!)