As (among other things) a consultant on strategic information systems issues to top managers of some good-sized outfits, I want to note that most Y2K hype is generated by people who stand to make a buck from it. The issue is real, but its two major effects on the general public are likely to be (1) shortages created by people hoarding because of the hype (that would not happen otherwise) and (2) frivolous lawsuits.

FF programs have been dealing with dates past Jan. 1, 2000, for a long time now - some programs for mileage expiration, the rest for award expiration. Airlines have booked seats into 2000 for over three months. It works.

Second, miles aren't going to "disappear." An FF database is a compilation of historical data. The data will still be there. The worst that will happen is that a program won't read them properly, so they could theoretically be inaccessible until that program gets fixed. If, in the absolute worst case, some obscure bug destroyed the entire FF database, airline computers are managed by pros and keep several generations of backups. (Clobbering the whole database, while incredibly unlikely overall, is more likely to result from something unrelated to Y2K than from the Y2K problem in any case.)

In terms of things to worry about, I'd put the Y2K effect on FF mileage accounts somewhere between being hit by an errant comet and finding a baby crocodile growing under your toenail.