Yeah, I think that the way it works is that there are only a very few factories in China/Taiwan that produce these aluminium or carbon fibre framesets. The big guys (Specialized, Trek, Giant, etc) give these factories specs/geometry/colourways/etc for frames that they want to be made for their brand. The factories probably sign a contract saying they will produce a set number of the frames and then ship them off to Specialized/whomever so that they can build them up and sell them. I guess that the factories can then take those plans from the big guys and make subtle changes so that they don't get sued (I am a little grey on this, perhaps suing in China isn't an option) and then run the machinery again and make a bunch of these great frames but without the high cost associated with a brand. I don't think that any of the geometry gets changed but I think that the welds might not be as smooth or perhaps they wouldn't use the same grade of material, but they are damned close to the same thing.

There are a couple of other people who sell these frames besides Bikesdirect, mostly on eBay but we all know that the Spicer entry level frame is the same as a Fuji Track bike which is the same as the Windsor Hour which is the same as......something else out there that hasn't been noticed.

There was a thread in one of the forums here about my road bike too, a Specialized Roubaix Elite, wherein this guy in Singapore was selling a whole bunch of the exact same frame for very cheap, one of them ending at under a 100$USD, great frame for a fantastic price. He also had some Langster S-Works frames for 255$USD, another great deal.