Last beta had serious wifi issues, seems to be fixed now.
But the Finder is giving me issues, two finger click does not show a sub menu, and it interferes with all Apps, for instance, when I was writing this post the sub menu shows up multiple times, didn't go away until I manually quit Finder, starts again now so it's not 100% Finder but it gets less, barely usable now.
I will try to start without startup Items, see if that makes a difference.
I have the wifi issue back now with DP7. .. With PB2 - no issues with the wifi