I'm not gone yet, but will probably be following suit soon. I've had Dish since Feb of 2000 and will probably be out in November when my current commitment ends.
When I left Comcast for Dish in Y2k, Communist Cast as I always called them was terrible. Terrible PQ, terrible service and HIGH cost. As the years have passed they have been putting a lot of investment in infrastructure locally, this year specifically (Project Cavalry) and now have a very good product to offer with excellent PQ that from what I've seen now surpasses Dish.
They also have a (mostly) apples to apples comparison on packages in my area to Dish. Digital Preferred (HD is included on everything now with CC) is almost dollar for dollar the same as dish...until you start packaging in Internet and Voice. And that's where my decision that it's time to switch comes in.
After Dish dinged us early this year with the receiver fees, I started looking. Until that time it would always come out a wash for me to have Dish for TV and CC internet over CC for both. Not anymore. Double Play from Comcast will save me almost $15 a month of the combined costs with no promos over my current Dish/Comcast combo. With the 12 month incentive pricing it's $60 a month cheaper, which essentially is 1 year of free Internet. If I bump to a 'triple-play' and switch my voice from AT&T...then my savings rises up to $80 a month (For the first year). After the incentives...it's still about a $15 savings from where I am today.
So yes, its a purely financial decision, brought on by the current economy. If Dish had just left well enough alone with the receiver pricing, I would have never even looked. And now I can't just turn away from the savings for a TV Subscription that I don't watch all that much anymore (I'm spend significantly more time gaming).