wow, many does not know all the changes in S60, V70 M/Y 2005....
Actually there are hugh number of changes, most of them are not visible as the visible changes in the exterior and new interior dash and center concole.

New particle filter to lower emissions in Dielse engines
New more confortable front seats
New door panels
New rain sensor
New radios, enables MP3 accessory introduced later this year
New CD players with anti-skip memory
New radio with preset buttons (instead of that turning knob)
Front parking warning sensor system as accessory
Active chassis as option (simular as used in S60 R)
Water repellant glass and mirrors
New T5 engine
New zero emission engine for California

Most big changes are in the electrical system which was introduces in all volvo models.
It is a completely new electrical system, just one of the changes is the puls wide modulation feed to the bulbs, which always give 12V regardless of the voltage of what the alternator is charging, this will dramatically improve lifetime of bulbs.