you still have more or less small to big problems with 32bit applications - but that obviously depends on your freeness level. If you don't use them, you have no problem at all…

If your cpu is 64 bit there is no good reason to be running it in 32 bit mode. Flash and wine work in 64 bit and if you absolutely need 32 bit apps that is possible as you know with 32 libs, but that is becoming less necessary every day. I don't believe 64 bit is any faster than 32 bit and it uses slightly more memory typically, but enables more memory to be installed on the system. I've been running 64 bit for 3 years now and even with the flash problem we had last year there were workarounds.

This means debian will be like windows 64 where you can install apps regardless if they're 32/64 bits? about time?

Yes something like that. Would be nice to simply install an i386 deb on your amd64 system much like installing a 32bit app on Windows

You can already do that (to some degree). Think of skype, flash and most other proprietary stuff. The packages need to be build in a different manner to cope with a few changes (different dependencies etc.), but the application itself were unchanged (how you should do that without source code anyway?). This is commonly called "bi-arch" or "tri-arch" as the space is limited.

This multiarch-thingy will allow in future to use the packages build for i386 straight on your amd64 machine. But also to install armel on sh4 or amd64 on mips… If your machine supports it of course to execute these binaries. But even if it can't a developer might still want to install these packages to compile his applications for this "foreign" architecture.

The bootstrapping for this change is ongoing, but very very early so it will need a few more weeks/months until it can be really used by endusers. But i can see a light at the end of the tunnel.
Lets hope it's not a train.

As I think about buying a new PC (intel sandy bridge i5) I also wonder if I should go for 32bit or 64bit aptosid. This will touch the decision for 4gb or 8gb of RAM.

As I understand this thread, you recommend to choose 64bit, right? The main problem is, that I need the adobe flash plugin for work. What is the best way to get this running on a 64bit system?

a) the 64bit flash plugin seems to be outdated.
b) use the 32bit flash plugin with a 64bit browser? Is this a stable and simple way to go? Or will it often break in dist-upgrades?
c) use the 32bit flash plugin with a 32bit browser. This seems to be the multi-arch topic, right? So there would be much manual work to get this working?

Which solution is the prefered one? b) or c)?

Besides of the maximum RAM usage of the system (I think about 3.5gb with 32bit?) is there any other drawback of simply installing a 32bit aptosid? Will all hardware components be supported the same in 32bit as with 64bit?

Thanks,
arwa