I have never ridden an 08 but, according the snowmobile magazines the 09 M8gets the most improved mountain sled award for 09.
There's a 22 lb weight drop between the the 08 and 09 for identical sleds. The weight loss came from all over the sled. Each part had to re-apply for its job. Some being from cross shafts and rear skid changes but most coming fron the deletion of reverse from the diamond drive (8 lbs).
One of the biggest differences is the powerclaw track. It works so well, it's like cheating but, some of the dealers are offering to install it on the 08s to make them more appealing.
The LE was a spring order only sled. They came in Black urban camo and I hear came with a factory Boss seat (but, I have seen some that don't have it). They also have a titanium primary spring and perhaps a front rear skid shock spring?
The Sno Pro and the LE get the Fox floats all the way around (except the front rear skid shock), the VSB telescoping handlebars, the white paint job and the premium gauge package.
Standard M8 153 466 lbs
Sno Pro 153 464 lbs (due to Fox Floats)
153 LE 456 lbs (due to Boss seat)
Add 2 lbs for a 162" track.
Good luck