most important of them:

*) Unicode character property 'General_Category=Cn' was erroneously ignored causing two related bugs in QChar::category() and QChar::isPrint().

As described in tr44, 4.2.8 Default Values
General_Category character property should be setted to Cn
for all codepoints omitted in UCD.
Instead they was mapped to QChar::NoCategory (=0) which have no equivalent
in Unicode specs and as result was ignored in filtering by binary mask.

*) reduce count of the unique unicode properties by fixing specialCaseMap entries uniqueness

this is a required set of changes on the road to Unicode 5.2.0 support