From a vendor perspective, the smart money should assume a strong Microsoft presence somewhere along the axis of e-mail, IM/presence and collaboration, and be prepared to play nicely with it.
This is extremely valid point. My bets are on e-mail in that formula. Vendors can't just rely on integrating their own solutions (or other products they offer) and ignore the 800 pound gorilla. Having a strategy for delivering tools that integrate with Microsoft desktop and productivity applications is vital to answering the needs of customers that don't want to overhaul their entire IT infrastructure. You'd have to have a pretty compelling value proposition to displace everything, and there are so many good enough alternatives in the marketplace today, so why not play nicely?
Oracle's Grand Collaboration Ambitions - Information Management Blog - InformationWeek