Comment 6 for bug 585940

IMO 32-bit will become obsolete within the next decade.
While there's little difference (some + some -) between 32 and 64 for most users, I believe having more people using 64 now is better for the community in the long term.
Shifting users from 32 to 64 will also shift bit-specific support and development (eg kernel) from 32 to 64, increasing the quality of 64, albeit at the expense of 32. Since 64 is the future and almost every 32 user will switch to 64 at some point, we should prioritize it.

As demand for 64 increases, the competition will be between Windows 64 and Linux 64. The more focus here on 64, the more users we'll get once 64 becomes the norm.

Myself, I've used 64 bit for 3+ years and the only problem is Adobe not supporting 64 bit for their proprietary flash, and the 32-bit wrapper crashing, although I think this is fixed now.

IMO, this warning is quite harmful and totally unnecessary.

I'd recommend rewording it to something like this:

64 bit: For all 64-bit capable systems (default).
32 bit: For those without a 64-bit capable system. (3+ years old).
(Check <here> to see if your system is 64-bit capable).