At this point, I'm about ready to make some observations on moving around these two fabulous cities.
My first thought is: if you want accessibility: go to San Francisco! I'm constructing four categories: bus, subway, taxi, and pedestrian.
I thought that this one should have been even, but New York is the clear winner.
In New York, more than one wheelchair user can board a bus at a time -- What? You think we don't travel in packs? Yes, we do have friends!! I tried to board a bus after my friend got on. I promised I would transfer, but the driver just wouldn't let me on: "It's for your own safety!"
In New York, I've never been denied boarding because someone else was in the space. New York bus drivers have to get up, flip the seat up, and then clip the chair in place, using four "tie-downs." They do so aggressively and resentfully, yes, but they do do it. In London, there's simply a space which gets filled with prams/buggies/strollers and other kinds of clutterances. In theory, people should yield the space, according to stated policy; in practice, hell no!
What's with the design of the space? In London, there are no tie-downs (which I thought at first was a good idea!). You just "apply the brake" and face rearwards with your head and back against this backrest (in case, you get smacked against the wall). It all sounded good. But I have no brakes on either of my chairs, and I've never found them particularly helpful for travel situations. I like to have a little roll so that the whole thing doesn't tip because it couldn't move in the even of a sharp turn or sudden stop. I like to control my wheels all the time.
Here, again, I thought things should have been more or less even. Both cities have a really small proportion of accessible stations -- though I think London may have a greater proportion than NYC, particularly if you include the outer boroughs. London's train to platform gap is much worse than anything I've seen in New York, even if you include the shifting platforms on the 6 or the way out S at Times Square/42. That said, London is the clear winner.
London produces accessible maps. OK, it's a chore trying to understand the thing, but at least you know which lines are accessible, in which directions and where accessible transfers are possible. In New York, you don't. In London, there are staff! People!! People to help you find the right place to board (which is signed, by the way) -- something like board here for level platform at x station. People to radio ahead so they can help you off, if the gap is large. Things are clean -- I haven't seen any piss yet. If you are brave and if you don't mind being yelled at, you can take those long, deep, scary escalators. Actually, I wouldn't do that alone -- I was scared by them when I was a nondisabled adult -- but they do exist.
No doubt about it. London is the clear winner! All taxis are accessible. You still have to hail the things (always a challenge), but they are accessible. No further comment necessary.
Both cities experience unbelievable tourism. Swarms and hordes of people travel en masse, blocking pavements, looking upwards, looking outwards, looking anywhere but where they are going. But tourists take cues from residents, and New York's pedestrian culture is better than the British one. Granted, both cities could use a couple more kerb cuts, but the issue is more about walking culture and spatial relations. New York is the clear winner here.
Even though the strollers are bigger and badder than anything I've seen yet in London (think Chevy Suburban to Austin mini), New Yorkers have a better sense of progression and of where they (and their strollers, dogs, kids are).
I think it has to do with how New Yorkers walk: much more focusedly and purposefully than the average Londoner, apparently. Londoners (and thus London tourists) walk more slowly, stop more, and are less able to stay in a straight line! London might seem to have a better sense of "walk on the left," where New York has traffic in all directions, but Londoners wander. Nay, meander. It's killing me. People! Just keep going and use your peripheral vision.
PS: Everyone keeps telling me New Yorkers are so friendly. Perhaps. Londoners are more polite.