Considering the signing of RVP is what most people credit as the title winning play by Manchester United last season, undoubtedly so. Especially when you consider this year their "big" signing has been Fellaini, who cost £3.5m more than RVP despite it being pretty unlikely he'll have as big n impact as RVP did.
The Champions League draw this year was very interesting. I for one expect the signing of Ozil to be key to Arsenal's campaign, but I still expect them to struggle. Given the teams in their group, I honestly think they'd be pleased with placing 2nd - Dortmund are going to be hot favourites to storm to 1st, and both Napoli and Marseille will give the Gunners a run for their money.