The case of the kay commonly follows along but, in and of itself, conveys nothing beyond kilo. A Kilo is still a kilo.
Ah, but when marketeers get ahold of it, then it's quite the problem of what a 'K' or 'M' or 'G' means. Just watch any of the computer help groups, and it doesn't take long for someone to start yelping that the hard drive the bought advertised as xxx GB shows up as only yyy GB. Allowing for the bytes that are lost to you from formatting and other overhead, the big difference is that the label on the box is using GB as decimal based billions of bytes (1,000,000,000) and most system functions use GB as binary based "billion" (1024*1024*1024 or 1,073,741,824), so fewer GBs show up.
Wouldn't it be great if some standardization could be agreed on, and used by all. Would save us at least a few KB of usenet traffic! (Or did I mean kb? I'm sooooo confused!) Val