This gets even more confusing because RAM and Flash Drives are sold in the binary equivalents while hard disks are sold in decimal values.
There's been an odd exception to this rule recently. After 64GB and 128GB (binary) flash drives, the next iteration is 192GB (binary) drives, and some marketing whiz realized that 192GB (binary) ~= 201GB (decimal). So this new generation of flash drives is universally being advertised as "200GB", rather than 192GB. Go figure.
To the nerds among us (I work at Google), the standard naming convention is to label the binary versions as "MiB", "GiB", "TiB", etc. (Mebibyte, Gibibyte, Tebibyte), relative to the decimal MB, GB, TB (Megabyte, Gigabyte, Terabyte). It takes some getting used to, but as you get into Petabyte and Exabyte territory they really start diverging, so it's useful for clarity. (Beyond exabyte, the next two steps are zettabyte and yottabyte, and the one after that is either hellabyte or brontobyte, depending who you ask.)
My reaction to this whole thread... It's universal for any marketer to ratchet up their advertised specs to the highest degree they can rationalize, because if they don't, the next guy will. So airfares are advertised with all the taxes and fees removed, food "serving" sizes are unrealistically tiny, performance of computer chips (in gigaflops/teraflops) is not practically achievable if you're trying to do anything useful, and you can't really drive a "200-watt" audio receiver at 200 watts, without destroying your speakers. (Unless you're playing a pure sine wave test tone in a vacuum. Yes, yes, I know.)
So since the Tesla battery cells can theoretically (under laboratory conditions) charge to 4.35 volts, and when you multiply that literal figure out you get 85kWh, Tesla can rationalize calling the battery pack "85kWh." The same logic goes for the "691HP", and also probably to all the other battery capacity figures from the other EV manufacturers. My guess is that the rationalizable limit for the "60kWh" battery pack might have been closer to 64kWh; not quite enough to be able to justify "65kWh", and then given that round numbers sound a lot nicer, they settled for "60kWh". If humans counted in Base 9, Tesla would doubtless have rounded these marketing figures to 63 and 81 ("70" and "100" in base 9, respectively), and then we would be arguing here about the 63 pack instead of the 81 pack.
To ordinary drivers, the EPA mileage figure is a lot more meaningful than kWh in practice, and I'm also glad their test allows driving the car past the "zero" point; it allows Tesla to set the zero point more conservatively without being penalized, which is better for drivers. And with 36k miles on my 2012 P85, my battery capacity has diminished perhaps 8% since new; I can still range-charge to about 242 rated miles on a good day. (~220 miles on a standard charge.) Lifetime efficiency is about 351Wh/mi, about 12% worse than the EPA rating. (21" rims don't help.) To me, all of this is completely and totally expected.
Just my two cents. Carry on