Maybe Overloud thinks it's in the same league as Altiverb, and are pricing it accordingly. That's a lofty goal -- will be interesting to see how it matches up.
Another competitive product, at a lower price, is HOFA's IQ-Reverb. Also convo-based but has lots of advanced features.
And don't forget the ongoing improvements in algo verbs -- Acon Verberate is fantastic, and for the budget-minded there are major updates to Valhalla coming any day now. Good times for verb fiends, er, fans.
Cheers,
Eddie
P.S. I tried to put links in here but for some reason I couldn't. Google 'em!