this is an upgrade offer over the phone. T mobile are offering £10/month loyalty discount if you upgrade your contract. I have upgraded my contract and got offered Combi 15 (300 minutes, unlimited texts) and Blackberry 8520 on 24month contract for £5 a month. (was also offered Nokia 6600i and T mobile pulse)
Total cost of the contract 24 months x £5= £120
Blackberry 8520 is worth around =£180+
this offer is not available online.
hope this helps somebody