Mountain Lion causes crashes on a MBP Mid 2010

Hi all,

just installed 10.8.1 on a MBP 15" Mid 2010 (i7 2.66GHz).

Every half hour of usage the System will crash (on the display I see fragmented menu bar and dock all around my desktop).

When it seems to be working if I try to take a screenshot (cmd+Shift+4) the curson will just go crazy and I will not be able to decide a starting point for my screenshot. And that's just an example of many wierd behaviors.

Downgraded to 10.7.4 every thing works fine, just like before.

Why do "they" say that 10.8 is compatible with my machine?

Why do "they" say that 10.8.1 will actually improve compatibility?

Why do I have to wait more updates in order to get things working on an older Mac (paying 10.8 months before)?

Thanks in advance.

L