I believe the OP might be talking about something similar to these packing cubes and having them assembled in a bag:
http://shop.eaglecreek.com/packit-wo...t/d/1144_c_211
If so, while Eagle Creek makes a good product they do have some areas I wish they were better:
1) They are not airtight and worn clothes can stink up my clean clothes if I travel to multiple places in a week
2) I have found they do nothing to compress the garments and remove air
My favorite product (by far) with a similar concept are Spacebags - but they seem to wear out so quickly (I usually have to replace them every couple months after weekly uses) if there was a way to combine the durability of the Eagle Creek product with the Spacebag concept of sealing (or at least containing) and compression I would be all about it.
Agreed with the clothes in a bag probably not having a huge market. Personal taste is just too personal - especially when you are going to be relying on the clothes to get you through everything while you are gone. What I do wish is that there was a great and practical travel "capsule collection" that was TRULY packable. The existing stuff I have found that works style-wise is made of unprofessional-looking fabrics (Spiegel) or the fabrics I like are not appropriately tailored (Chicos, TravelSmith).
Brooks Brothers makes perfect travel shirts (their wrinkle-free shirts are a lifesaver and look VERY nice, even after many turns through whatever questionable laundry place I send them off to) and Ann Taylor will occasionally come out with something great that packs and unpacks well - but for the most part it is a game of mixing, matching, and much more ironing than I would like.
Male road warriors seem to have some great options - I wish the same could be said for us! I'd love to have a suit where I don't have to wear the jacket on the plane and press the bottoms at the hotel. Bonus points if I could buy some wrinkle free, machine-washable silky tops that match a cardi which also matches a shell and coodinates with a wrinkle-free button-down - that also doesn't look cheap compared to the stuff the boys are wearing (yet again - Spiegel has a great concept but the quality just doesn't cut it when I have to interact with execs)
Until that sort of a collection exists I will carry on as I am.