I wasn't sold on him, but after thinking more about it, I think Delph could be a very good signing. He gives us the one thing we always thought we'd get, but never actually got with Milner - energy in the middle of the park. Milner was rarely trusted in the middle, I'm not sure why, but he was nearly always used out wide. In games against bigger european possession based teams, we've been crying out for another all-action Fernandinho type player, with bundles of energy - which many thought Fernando would provide before we realised his legs don't allow him to enter a full sprint.
He won't be an instant starter, but if Fernando was somehow allowed to start some games this season, I'd say Delph is capable of showing the quality and determination to start double the amount.