Yeah, I've been using the 64-bit flash since they released the first alpha years ago and it has been (for me) as good as flash ever is.
Note: I browse with flashblock on, because most flash annoys me. However, I have rarely encountered problems that I can attribute to flash. With the first release of Fedora 12 flash video caused a crash but changing from the nouveau driver to the nVidia driver fixed that. I can see youtube, dailymotion, etc, and all non-video flash sites work fine.
Sure, non x86 or x86-64 platforms are not as lucky, but that's a fairly common problem with those architectures: proprietary software doesn't support it. Heck, most Free software doesn't support it as a first-class platform, but dedicated users of those platforms can usually make stuff work.