During the cycling season, I sometimes bike up in the mountain roads of Santa Cruz County with my GPS. I'll try to upload my tracklogs whenever I do so, since it seems like that could be a very useful resource for making these tree covered roads more accurate in OSM.

POC stands for Pedestrian Overcrossing. They are small bridges for bicycles and pedestrians that cross over major barriers like freeways. If you live in the Bay Area, one new, prominent example is the Mary Avenue Bicycle/Pedestrian Overcrossing in Cupertino. It is a long span suspension bridge that crosses over 280, just east of 85.

I guessed that this was the convention based on the tagging of a couple of local airports, as well as the Mapnik rendering of these aeroways. The ones tagged as aeroway=airport are rendered more prominently than those tagged as aeroway=aerodrome. This page suggests that there is a legitimate distinction to be recognized here, and that the emerging airport/aerodrome convention seems like a reasonable way to represent it:

osm.wiki/Talk:Mapping/Features/Airport

Yes, I agree that the place designation should be determined by relative importance rather than just size. And it was also for that reason that I upgraded Willemstad to city and downgraded Kralendijk to town. Having visited it recently, even though it is the capital and most important settlement on Bonaire, it's just not a city! :)

For what it's worth, I think both proposals would work and would resolve the deficiencies of the highway=stop tag, but I personally find it more intuitive to specify the stop sign via way and a node, since the way and the node node are natural participants in the junction at which the stop sign occurs, but if you specify the stop sign via two nodes, the "from" node could be quite some distance from the intersection, and the stop sign could become undefined if that node gets deleted.

Yikes! I'm not sure how I missed that! Thanks for the catch. Second Willow Glen removed!

For anyone who is curious, the area where all the traffic diverters is located is here:

http://www.opencyclemap.org/?zoom=16&lat=37.33824&lon=-121.87424&layers=B000

And the area with the inexplicable change in the bike lane is here:

http://www.opencyclemap.org/?zoom=17&lat=37.36096&lon=-121.89661&layers=B000

The bike lane is not part of any designated bike routes that I'm aware of, strange as it is I'm leaving it as is, with one short bit without a bike lane.