Here is a link to a great talk Konstantin Ryvkin gave at the Redmond Interoperability Protocols Plugfest this past June on Exchange in Office 365 Dedicated:
I’ve been working with Kostya on a number of partner engagements lately. This is a great depth understanding of Exchange Online in Office 365 Dedicated, how it is delivered to customers, and what that means for partner solutions. Dedicated is a very unique beast as compared to Exchange on-premises or even Exchange Online as part of Office 365 Multitenant/Shared. If this is a target environment for your solution, you should watch this presentation.