Thankfully, the Android side experiences very little "arms race" since the ARM's tend to be very efficient even at low MHz. (Har har) I think people are far more about what the hardware can support and DO than about how fast it can do it, most of the time, since the OS seems to run surprisingly well even on low MHz devices so long as you have enough RAM. RAM and memory management seems to be the only REAL problem and most of that is conditioned VERY well with the V6 Supercharger or with newer versions of Android (i.e. 2.3.4 is GREAT for battery, task and memory management).

Yup--most of the 2.x updates have almost entirely been under-the-hood, but MAN you can definitely notice and feel the difference from one version to the next, despite the visual/UI similarities.

Not entirely sure what you mean, but every device has to have firmware made for it individually. Just as you can't run Maemo 5 on an N8x0 device, and you can't use N8x0's OS2008 on an N900. You need to compile the firmware to handle each device. Additionally, Android (and the Dalvik virtual machine) run on MANY different processors--so you also have to target your ROM build for those different architectures altogether. Thankfully, once you get all the ROM stuff out of the way, the apps should generally run without regard for any of that because of the virtual machine running on that platform.

I'm very thankful to my past-self for not hanging on Nokia's numerous promises. You certainly COULD be forgiven and it's understandable--but, especially in this thread, you're among like-minded ex-Maemo (or still current-Maemo) users who can relate. Don't apologize.