“Porting and device fragmentation”
Well – most of this comes down to hard coded vs. dynamic screen size – as a old school java developer you had the chance to get the actual screen size from the device and adjust your screen layout dynamically. It’s not only related to screen resolution – even in OS 4.x you should adjust your display based on the selected/configured default font size.

The ONLY issue I personally had with new devices are more or less issues with the OS updates itself – where functions that had previously worked rock solid was broken (and declared by RIM dev support as “intended to work this was”) – Most of my adjusmnets I had to do for new devices (or better for new OS) had been patches & workarounds for the OS istelf.

BB10 will of course first come with a single screen size – but I am confident if developers does not pay attention in the same way that should had with the previous OS, then they will run again into similar issues.

“Installation Difficulties”
At least we had something useful to install on our old BlackBerry Devices…

“BB-Browser’
*big sigh* – first one that was actually some sort of useful was with OS6 (e.g. to init o-auth requests)…
Interessting to read, that you use your Playbook as some sort of Laptop replacement – each time I decide to pick up my Playbook I have to plug in the charger first and wait 10min till the thing have rebooted… Even my old Pentium 90 can boot faster it’s Win95…