The Sun acquisition almost certainly will create nasty channel conflict problems for Oracle. It will be tough business for Oracle to sell end-to-end hardware and software that competes with its OEM and channel partners. Some of them will seek refuge elsewhere. The channel conflict is a sales opportunity for Microsoft, which is notoriously well-known for its partnering. The company shies away from channel conflict, particularly something like buying a server hardware company.
Perhaps most interesting of all will be patents. Microsoft and Sun have cross-licensing agreements that might not carry over to Oracle, depending on how the agreements are written. Neither Microsoft nor Oracle might want to continue the agreements anyway.
Similarly, there is Sun's status as a Windows Server OEM. Would Oracle sell Windows Server? Sun didn't move enough volume for OEM licensing to even minutely hurt Microsoft. But it is one of the main questions that must be answered over the coming months.
Joe Wilcox is editor of Microsoft Watch.