Di Matteo did a great job winning the two trophies that he did. However he acheived that by letting the team revert to the compact, solid and narrow type of play that they have always played since the Mourinho days. They executed their game plan against Barca and Bayern perfectly but none of the stuff they produced was the progressive brand of football Abramovich seems to be seeking.
Whilst they are undoubtedly going to have a good set of players in the coming season, it remains to be seen how well Di Matteo will do at creating a new side and a new style of play. Essentially he will be attempting to do what AVB failed at, although admittedly with a different set of players.
I still think there are doubts about the manager, and with lots of change in the playing staff over the summer, most notably the departure of Drogba, I don't expect them to push us and City close for the title although I expect them to qualify for the Champions League