I do agree with you that there are not as many 64 bit, and multicore
capable programs as there should be.

We've had 64 bit processors for how many years now? And multicore
processors are not that new. Yet 64 bit operating systems are still
not dominant, and programs still have issues with them. On my win-box
I've been using F-Secure for virus protection. When I upgraded to a
newer machine, it came with Vista 64. Guess what, F-Secure is still
not 64 bit ready. Went with Avast which is, and now I have a nasty
little virus/torjan downloader that maybe after buying yet another
program to rid the machine of malware, I might finally be rid of.
(Haven't had an alarm in over a week, but it took two weeks and
multiple deep scans to get rid of it, if indeed it is really gone.
Which is another reason why I like Linux.)

But even in the Linux world, 64 bit versions are not as reliable as
their 32 bit brethren.

Ahh... but help is on the way. According to the Science Channel,
within 10 years they expect computers to become self aware. At that
point they will be smarter than us, faster than us, and will write
their own programs and eventually decide what we need and possibly
whether we should even continue to exist. (Sure hope that self aware
machine is based on Linux. If it comes from Microsoft, be very
afraid.)