Take the $29.99/mo x 12 + $44.99/mo x 12 mo dvide by 24 mo = $37.49/mo if that is acceptable rate for you, then go for it.
In most cases if you get more services (phone, internet, cell) from the same company you get discounts. So, comparison shop for the whole package.
Time Warner only charges $29.99/month per service if you get all 3.
Just for comparison, we pay $66/mo for Verizon FiOS triple play (PrimeHD TV, 20/5 Internet, local/long distance/International phone), comes out to $23/month per service.
6 TV's in the house on FiOS and we only pay $4.99/month to connect them all!!! Power to the CableCard and WMC7!!!