Usually we would have to define a metric in which we can messure 'success'
(or the lack of), first. And let me tell you, there are many valid metrics one can
define. Of course there is the trivial metric, investment vs. profit, but this metric
can be rather shortsighted.
It's obvious that any further support depends on whether WipEput HD is a
success or not. How many copies were sold? Judging from the leaderboards of
SR, TT, SP; all at VINETA K, VENOM speed; and ZONE a tight upper bound can
be estimated. We have about 240k entries on these leaderboards (date: 08/01/04),
hence 240k copies of WipEout HD were sold, at best, up until today. What does
this tell us? I don't know.
Personally, I consider WipEout HD as a success according to my very own metric.