It should be noted right off the bat that supplies seem to be going quickly. HTC is already listing the 16GB variants of the Nexus 9 as "Out of Stock" (they had been selling for $239.40). So, that means, you'll have the choice between $287.40 for a 32GB Wi-Fi only model or $359.40 for a 32GB LTE model. The Wi-Fi only is a choice between black or white, but the LTE only comes in white.
These are still some killer prices, because the 32GB Wi-Fi model sells for $479 in the Google Store or $370 through Amazon, while the LTE model would normally run you $599 through Google or $499 through Amazon. Of course, as noted, stock is already disappearing, so while the sale technically runs until 11:59 PM PT on Wednesday, November 4 (tomorrow), there's no guarantee supplies will last that long.