Upload & Sell: Off
Very early on there were limitations, I mean with my Kodak DCS-560, limited to 200 ISO, but otherwise 1fps, 3 frame buffer, 250-300 shots per battery were all workable, not a big deal that prevented me from delivering the goods. But even at the time ISO 200 was not that big of a problem since most of us were shooting Kodak PMC 400 anyway. I also had a DCS-520, which let me go to ISO 500 or 800 perhaps and get good files and the two cameras made a great wedding kit.
The Canon D60 was a nice step up. The speed and ISO range of the 520 with the 6MP file size of the 560, and dirt cheap at $2500.
After that it's been small changes, the 10D was no big deal, mainly got even cheaper and slower, then the 20D was nice, had those for years and made a tone of money with them. After that I bought a 1DsII in 2007 I think. And guess what? Still using it as my main camera. I bought a 5D II and sold it after 2 months, looked at the 1DsIII and even the 1Dmk IV, which is a really nice camera, but for me did not offer enough new features to justify the investment. Now the 1DX is in my sights since me 1DsII is nearing 300k exposures.
Do I need it? no, but the higher ISO capability will be useful for me with todays reception room designs, and being able to shoot small RAW files will be nice, but I have no reason to think that I won;t be able to still deliver top quality work with 1 pair of 1DsII and a 1DII camera. They work great