I have seen a number of individual postings discussing the relative merits of particular aircraft operated by particular OW carriers. These discussions are very helpful but I have not found a site that summarizes this information. What I have in mind is a table that would provide evaluation in either the form of text or ratings for the different components (seats, food, etc) for each OW carrier and each type of plane�and supplementary information if it is very route specific. So I want a meta-level seatguru that is directed at helping me choose, for example, whether to fly CX from NRT-HKG on a 744, 733, or 330 rather than which seat to choose once I have selected a flight. I realize that these evaluations would be very subjective but so are evaluations of particular seats. Any suggestions about where to look?

Probably FT is the best place for information. There are always lots of changes to aircraft configurations, offerings (aircraft type and longhaul/shorthaul variants, etc) on various routes, service, etc.

Start with the airline forums. The alliance forums can also be good with comparisons - especially where routes are served by multiple airlines.