Actually the prices are down by quite a bit from a couple of years ago, as are most but not all collector cars.
A notable exception is Ferrari, which have been slowly gaining in value, even in these challenging economic times.
Two years ago Boss 429's were averaging 330K, and there are documented sales as high as 650K, although these were few and far between.
I have an early 69 which I have been restoring over the last two years, about 90% completed, which I would gladly sell for 125K. Missed the boat when they were at all time highs, but hopefully they will get back there again when things pick up.
The car in question is arguably the finest Boss 429 on offer currently, and probably one of the top 5 best ones out there.