@Chris

Safari is by default 64-bit in OS X Snow Leopard, but is thankfully able to use existing 32-bit plugins so you don't need to wait on anyone.

I would ask Flash to do any 2D stuff, never talk about 3Ds...

Is killing my machine(s).

@MattFlashedOut
As much as I am tired of flash and have flash-blocking software within my browser, to say they are procrastinating with a 64-bit build is not really fair. One major problem is that you must use a 64-bit browser to install it onto, right? And today those types of browsers just are not mainstream. I think only recently did Mozilla come out with a 64-bit version of firefox, but there aren't any plug-ins available for it yet since the original 32-bit versions of them won't work. I know with Vista, there was a 64-bit version of IE installed (for the record, I never use IE) but the couple of times I did use it, I recall not being able to access some websites and had to use the 32-bit version instead. I think, perhaps, Adobe found it more logical to wait until 64-bit browsers (and websites) become more mainstream before allocating resources into that development.

As for 3D flash, that means it's only a matter of time before everyone is hit with (useless & annoying) 3D Flash ads.

Ok, I thought Adobe explicitly stated last year that 10.2 was going to be focused on upgrading Flash to a 64-bit application. It was indicated that once 10.1 with the hardware acceleration was completed, 64-bit would be the focus.

If they're now saying that 10.2 is going to bring about 3D, I find it unlikely they will develop 64-bit alongside......

Sure HTML5 does 3D, most of the time that's just playing a video that's encoded for some format, doesn't matter for the player really, only when you need syncing signals it becomes an issue, but I'm sure that's trivial to add.
Pre-v10 youtube already does 3D btw, in anaglyph and interlaced and side by side as I recall, so it's really only the syncing signals, which you could extract from the video and make available for the glasses to sync to.