Sky is offering LLU ADSL (used to be Easynet).
First thing, check
www.samknows.com to see whether your postcode has unbundled ADSL coverage and what speed (eg my address is in theory covered by Sky, but due to a 4KM run to the exchange I would only get 512Kb ADSL

)
If you are within range of an LLU exchange, the Sky offer is for Sky Digital customers and you need a BT phoneline. You need to cost up BT Line rental, Sky installation and TV package, Sky unlimited call package (£5) and then the broadband charge.
Bottom line - it 'might' be a good deal, but if you currently have the NTL 'triple play' (BB, Phone, TV) it will be a loat of hassle.
The Sky deal is being discussed in more detail elsewhere on here - try 'Sky Broadband' in the search box

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