But still, if you're one of a very few people who care about this kind of detail, how are you going to incentivize everyone else to collect this info for you, especially when Hilton family hotels are less likely (compared to 2-and-3-free-floor midline chains that have their rooms spread out in incomprehensible mazes, like some Comfort/Quality in the Choice) to even GIVE OUT floor maps in my experience.

A first step would be for everyone to get everyone to collect a floor map from every hotel they go to, scan it, and submit it to some website you start up (and fund!). There'd have to be a "reward" of some sort for this hassle; are you up for buying points or miles in bulk that you can give small amounts to for each useful submission? Then once there was a map, there should be a focused comment area (Wiki or traiditional posts) for additional info for a hotel for which there is a map.

It would presumably take a really long time for info about specific rooms that YOU end up able to choose to be added to this. So you have to start it knowing the payoff that helps you specifically may take a while. (It'll depend on the overlap of properties stayed at between you and the other contributors, as well as the room type preference overlap between you and the other contributors.)

Now here's the clincher: Scanned existing hotel floor maps are the only FAST way I can think of to get this going, but they require a lot of storage (once you start collecting a useful number of hotels), even if you restrict it to Hilton family (but if you restrict it to Hilton family, a lot of people who stay at various other chains and Hilton family only SOME of the time might not both to help). In particular that's ORDERS OF MAGNITUDE more storage than sites like seatguru or expertflyer (or even maybe FT) need! How much is this storage going to cost? (I'm not up on how much oodles of storage on a web site costs these days.) You could reduce the storage drastically by re-entering the info in some parametric (rather than graphic format), if you want/need to save storage space, but who will have the time and resources to do that?

So, again, you've got to balance this against the cost to you of calling the hotel EACH TIME you see a room available on eCheckin and asking about that room, asking THEM to fax the floor plan to you, etc.

In fact, if you did have a web page to put all this stuff, there'd be nothing stopping YOU from calling EVERY Hiltion family hotel in the country and asking EACH ONE to fax you their floor plan. (I'm assuming here you'd use a fax number that converts to a file rather than one that prints on physical paper.) You won't know until you try how successful you'll be. (You might be surprised at how much historical info in certain fields now exists only because some ONE person sent out blanket requests within an industry years ago and actually got results aplenty, and that person archived what they got back.)