I see no reason why there can't be an option for using both kilobytes (1000 bytes) and kibibytes (1024 bytes), like the labels here that say something like "1Gal. (3.8L)." Slowly people will begin to understand the relation between the two, like how many people learn that a yard is almost a meter.
As for sounding ridiculous, that's just ridiculous. They may sound funny, but so does the mole (mol) and the joule (J). In fact, my chemistry teacher in high school had us make a mole (the animal) for a grade!
Once again, the drives could use the metric standard and the binary standard, as in "500GB (465GiB)," allowing consumers to see the difference and keep them happier with the manufacturers because they knew the two possible measures that could be used, instead of feeling they were ripped off.
In the programming sense, using the standard 10^x is rather an annoying convention because of the nature of bits - 0 or 1. If they were to somehow come up with a 10 state bit (easily possible with quantum computers,) then I could see the warrant on using the standard metric definitions, but until then, no thanks. This difference in systems - base 2 instead of base 10 - led to the rise of other counting systems, such as octal and hexadecimal (hex). Personally, I like to count memory and the like in hex in the binary notation. In hex, this use of "strange" numbers tacked onto the end disappear. For example:
1024 Bytes = 0x00000400 Bytes = 1KiB
1024 KiByt = 0x00100000 Bytes = 1MiB
1024 MiByt = 0x40000000 Bytes = 1GiB
It also comes in handy to use the KiB notation in small systems, where you need to know exactly how much memory you have left and if it's enough for a 4KiB image.
Oh yes, the reason we use binary measurements is because comuters use binary! Addressing for both RAM and hard-disk is done using the binary/hex system. That being the case, it makes sense to me that they use the binary versions of the prefixes, but that would confuse people. So once again, I think listing both notations on the package makes plenty of sense.
Not to mention, if a byte were a standard SI unit, then it would be made of 10 bits. Then you could have a real decibyte. But naturally, if there was such a change, all the software out there right now would wind up being pretty useless because it isn't built for 10 bit architectures (although that can fairly quickly be remedied).
In the end, I think placing both labels on products will help get people used to the relation of a GB and a GiB. I have started to be able to tell approximate size of large files from one system to another, similarly to the conversion of yards and meters.
Anyhow, that's what I think.