To go into more detail on the above, here are my general preferences and what I think is optimal gear weight vs. skiing style....I think they can apply to pretty much any advanced to expert skier, and you will notice a difference. Keep in mind everything is relative. You also can't really talk about ski weight without considering length, a long ski will feel heavier in swing weight.
Bumps: Light binding, light to medium ski.
Trees: Light to medium binding, light to medium ski
Powder (all around): Light binding, medium/heavy to heavy ski
Powder (high speed): Medium to heavy binding, medium/heavy to heavy ski
Freeskiing (Do everything): Light/medium binding, medium/heavy ski
Freeskiing (High speed carving bias): Medium to heavy binding, medium/heavy to heavy ski
Freeskiing (short turn carving bias): Medium to heavy binding, medium light to heavy ski.
I'm 190lb, 6'1", and a strong expert. For the above, here is what I would consider heavy, light, etc, and specific models I like. If you are bigger or smaller than me, you would have different perceptions of weight. (weights are per pair)
Light - 4-4.5lb. 957 Composites, FKS 120, p12. Most 12 din bindings
Medium - ~5.5 lb. P18's, most 14 din bindings.
Heavy - 6.5-7+ lb. S916, sometimes with lift. Other race stock. Atomics. Setups w/Plates.
Light: 7 to 8.5 lb. Any skis without metal, 180 to 195 cm, any width. K2's, etc.
Medium: Around 9 lb. Skis with metal, wider, light to medium weight core, 180cm to 190cm. Or narrower (<80mm waist), with a heavy core, metal, 175-190+ cm. Im88's, 186 LPs, Mantras, metal/wood carvers, etc.
Heavy: 10lb+. Heavy metal, heavy wood core, wide, 180cm to 190cm. Or, 190+cm, medium metal, meduim to wide, medium weight wood core. Big stocklis, 194 LP's, P+'s, Titan pros, etc.
Obviously there are exceptions, but think these are pretty good guidelines.