A comment / question about System Value: I'm a Canon shooter, so it's the only system I know. In the last few years, Canon has slowly released updated versions of its lenses. This was done in an effort to enhance the performance with sensors, rather than film. So in that sense, there's unspoken value in a newly assembled Canon kit.
To what degree are other manufacturers releasing digital-optimized lenses? Are all the new Sony lenses already "optimized" for digital? I'm sure their marketing people would say "yes". What about Nikon lenses? Are those still the same lens designs form the film days? I expect the Leica S2 (and the subsequent R10) will be designed from the ground up with sensors and their inherent design issues in mind...
All new lenses from Sony regardless of whether they are standard lenses, G or CZ are 'optimized' for digital - as are now 'new designs' (all the Minolta lenses that got carried over were released at the time of the takeover, which was a number of years ago). Sony has never produced a film camera hence 'digital' is all they know. Even the lenses like the Sony 50mm f1.4 which were based on the Minolta lens - was given 'digital makeover' (see DPR who compare thr Sony lens to the older Minolta). All 'new' Sony FF lenses will be designed around the 25MP a900, since this is the only FF camera Sony has made.
Film was a long time ago and I would expect it's not whether they are 'digitally optimized', it's whether they are 'high resolution optimized'. Whether they are 'high resolution optimized' will depend on a number of factors, the generation of camera was around at the time of release, what was in the pipeline for release, and the target cost of the lens. I'm sure are lots more factors, but that's just a few. And the more lenses in the range, the more that need updating.
I'm sure there are lenses from Canon, Nikon & Sony that need a 'makeover' for the higher resolution cams. In fact I know there are, just talk to a 5D2/1ds3, a900 or D3x owner with a reasonable amount of kit and they'll quickly tell you what lenses work well, and what they would like updated.