With my first voyage into Sharepoint BI, I was both excited and apprehensive at the same time. But, I quickly fell in love with the first impressions, and the ability to really have a method of deployment of some of our BI capabilities. Scratch under the surface, and you find alot of "buts" . Connecting document libraries to Outlook are a great feature, but ..... Easy deployment from BIDS to sharepoint is easy but.... And for my latest investment in time, the missing default option for date parameters. Will keep you posted on how this pans out.
Quick follow up: Simply shifting the date parameter up the hierarchy sorted the issue out. Now you can select the "Use Default Value " checkbox.