Imo, the question that I'd ask before making a decision is, what kind of programming do you (or family members) prefer? If you're wanting the maximum sports coverage, there's no question that DTV is the way to go.
If you're primarily interested in the most movie channels, from what I've read here, Dish seems to be the leader in that category. However, as you may be aware, DTV recently launched a new bird that's about to go online which will add more movie channels and also add more of the "national" channels (ie, Travel Network, WGN HD, etc) into DTV's programming choices. I'd recommend waiting another month or so and see how DTV's new sattelite expands their channel choices.
As primarily a sports fan, I can tell you that there's no choice but DTV in that genre. They have MLB EI, Sunday Ticket, and more overall sports coverage than Dish. That's why I've been with DTV since '99 and it's also why I've never considered Dish as my provider choice.