said by en102 :

I tend to agree. There's no real benefit.

Comcast = pricey Cable provider with caps on data
Sprint = cheap Wireless provider with limited coverage (without roaming) and no caps on data.

Comcast gobbled up Adelphia and swapped markets with TimeWarner in some areas and is doing ok (and increasing prices all the time).
Sprint merged with Nextel, struck a deal with Clearwire on WiMAX and is struggling with keeping subs.

I don't think these 2 companies would work well together.