I think they will be a lot of good quality well priced used bikes, and a load of crap ones also. People might keep hold of them a while as mentioned above, but I'm sure some people will sell, more so if it's a decent one and worth a decent amount of cash, before it gets older and depreciates. I've been trying to get a mountain bike for my daughter and it's been very hard to find stock anywhere, hence while they'll be a lot of bikes after this, when a lot of people go back to being lazy. Luckily I found a Liv mountain bike in a local shop, by good fortune.
I'm pleased that bike shops haven't been hiking up prices to cash in etc. People seem to be trying to do that on a well known auction site with used ones, I just gave in looking and bought new. I'm going to put my daughter's Specialized Hotrock 24 up for sale, looking at other ones to get an idea, a lot of people seem to be taking the p1ss for worse examples than this one. I'll just sell it a fair price, can't stand that kind of thing.
I've got a Concept 2 rowing machine that I use at home. Just out of curiosity I looked on the same auction site at these, I have no intention selling it, just bored. I could get more than I paid for the machine new 3 years ago. I googled it again out of curiosity and you don't appear to be able to buy the machine anywhere. It was just a quick search though, but explains aution prices.
It would be good to think that people will stick to this fitness regime, or possibly gym memberships may fall, as people have been forced to find other methods. I guess somebody that buys an expensive rowing machine is fairly serious. I just bought it as I can't stand going to gym's.