Elisa wrote:red123 wrote:...
The new KDE can be upgraded even in the KDE-Mint-9 as I did mentioned above...

Sure, you can do this. But in my opinion the nice thing about Boo's work is the Themeification. Mint 9 KDE looks very nice. And upgrading to 4.5 is like going to Ubuntu. And in my opinion, if oyu are gonna have Mint looking like Kubuntu, then go for Kubuntu.
I've personally went to Kubuntu for this release. On one hand 10.10 is very nice. Then, I'm didn't want to wait for Mint KDE 10 anymore, and third I wanna have KDE 4.6 when it comes out. So even if Boo released today it wouldn't make sense for me to have Mint installed for two weeks.
Why KDE 4.6? I think it is pretty much common agreegent that each KDE/Amarok release is better than the previous one.