Vitamix has been selling reconditioned machines for a while, but they just made some new models available. I think these are a great deal, as they come with the standard strong Vitamix warranty, just 5 years instead of 7. If the warranty is an issue for you, you can extend the warranty to 8 years for $75, which is less than the savings. Reconditioned units are tested and repaired if necessary, and come with new containers and tampers.
The 7500 (aka Pro 300) is the new model that they released last year with the shorter/wider pitcher, longer blades, and more powerful/quieter motor. Sells for $529 new.
The 6300 (aka Pro 500) has been around a bit longer and is the same as the older machines except it has preset modes. Vitamix is selling it for $649 new, although Costco sometimes has it for $500.
If you're confused about all the different Vitamix models, check out this page:
If you have an old Vitamix, they'll give you $100 for it with their trade in program: