I actually think that the delay of Froyo won't be as painful as with Eclair. Numerous reports I've read online from Google employees have stated that what they're trying to do now is isolate parts of the OS as individual downloads in the Market, that way they can cater to older/newer devices and get some of the newer features out sooner rather than later. For example, a flash-compatible browser could be put up in the Market, instead of updating entirely to 2.2, but only available to hardware that can handle it (think Google Earth/Live Wallpapers for Android). This would also make more sense as stand-alone app downloads to avoid big delays from 3rd party skins, such as Sense UI, or carrier approval. Also, with the wide array of hardware specs on Android devices (even newer releases), Google has a chance with this method to deliver as many up-to-date features as possible, hardware permitting.
I honestly think this is going to be the case going forward. I think 2.1 is going to be the minimum software specs, and then this per-download method will be the new thing. Think about how many Android headsets have been "miraculously" updated to 2.1 in the past month or two? Google has something up their sleeve, and I can't wait to see it at I/O!