+1 to everything Rodney said but there's a few differences from the 2002-2005 and 2006-2010 models.
The second group, 2006-2010, the changes were as follows:
- Vtec engagement was always 6800rpm and disengagement was 6600rpm. This was changed to 6400rpm engagement and 6100rpm disengagement. It's a lot smoother in the 2006+
- Upgraded wiring harness as some of the wires were too skinny and the connector would actually melt or burn through R/R's. However there was a recall for all previous years to fix this, so you can always get it fixed in prior models.
- Clear lenses all around.
- ABS is standard.
- Gradient tinted windscreen.
- Half white tach.
When Vtec kicks in, some either love it, like Rodney, and others hate it, like myself. This is why I bought a Power Commander V and now the transition is so seamless that you don't even notice it. The addition of the PCV really smooths out the bike and performs how it should have from the Honda factory.