I was trying to compare the geometries of a Bianchi Via Nirone 7 & a Specialized Allez the other night, and not having much luck because some of the measurements & notations each mfgr uses is different.

It got me thinking that it'd be neat if there were a website that was basically a wiki-style database of all the different measurement values of various frames. For each year/model combo, there'd be a list of fields for different measurements, that people could fill out either based on info from the frame makers or their own measurements. Each value could be rated for its level of accuracy, verified by other people, etc.

There'd be as many values available to list for each frame as manufacturers as are commonly used by frame makers. Other possibilities include side by side comparisons of frame geometries of user selected year/model/size selections, and ability to select a frame whose geometry you like and search for other frames with similar geometries. And scaled geometry drafting/design pictures so you could do visual comparisons.

Thoughts on the viability/feasibility of such an idea, ideas on other possible options, etc?

Sure, if you can find somebody to do the programming and pay for the hosting. What would be almost as useful (and way cheaper) would be a simple stack/reach database with user measurements.