I've not opened a full catalog in the Beta but rather just transferred a bunch of images to play around with. I haven't noticed anything out of the ordinary in terms of speed (or lack thereof). I printed out a couple of things from the print module today and it worked fine. Because it is the beta, it did not import any of the presets that I have in LR 3.6 so I had to go through the trouble of setting up the print size etc. Once I hit the print button it ran as fast as LR 3.6 in terms of rendering and sending it to the printer.