Source : Free On-Line Dictionary of Computing

heatseeker
     
         (IBM) A customer who can be relied upon to
        buy, without fail, the latest version of an existing product
        (not quite the same as a member of the {lunatic fringe}).  A
        1993 example of a heatseeker is someone who, owning a 286 PC
        and Windows 3.0, goes out and buys {Windows 3.1} (which offers
        no worthwhile benefits unless you have a 386).  If all
        customers were heatseekers, vast amounts of money could be
        made by just fixing the bugs in each release (n) and selling
        it to them as release (n+1).
     
        [{Jargon File}]
     
        (1996-03-12)