backwards compatibility

Imho boud was a bit too enthousiastic there. It took us 3,5 years to go
from 3.0 to 3.5, and we're just 18 months into the KDE 4 series. We surely
haven't fleshed out things as much as we did with 3.5. But he is right in
that development speed is enormous - we've doubled the number of active
commiters to the average release over the last 3 or 4 years, and that's
huge. While this release was all about finishing stuff, it's far from
done. There will surely be issues and things which need fixing. Then
again, 3.5 was far from perfect either...