I don’t normally like to repost stuff to death, but something that could be missed in the flurry of Office service pack 1’s that have been released today is the SPD SP1 release. I just installed it in my local SharePoint Designer instance and so far I haven’t had any problems (though I admittedly haven’t put it through the paces yet). It seems slightly more responsive though that may be just a placebo affect. If you have any remarkable positive or negative upgrade outcomes, post a reply here.