Something's changed!
Out Of The Box, 2010 KDE Beta2 found my HP B109a photosmart printer/scanner. It scanned and printed correctly, and the HP Device Manager worked.
However, with 2010 KDE final, on booting, it says that it has found my printer and has set it up. But it hasn't!
There's no printing, XSane can't find the scanner, and HP Device Manager says that 'No installed HP devices found'.
Although I can't get the printer/scanner to work, this posting is mainly to point out an apparent change between the two versions of 2010 KDE.
I've had to go back to Beta2 in order to use my printer

Cheers
Keith