Ever since I was an investment banker at JPMorgan supporting their Software M&A team, I was predicting that the future of products and services in enterprise applications is inseparable. Significant portion of our team M&A advice to product vendors was to beef up their services portfolios and vice versa. These were my thoughts then, that are still very valid today:
CXO engagement. It's much easier to approach a C-level executive during a strategy initiative, which traditionally is the realm of strategic advisory and management consulting firms. The earlier you get your foot in the door with a CXO, the higher are the chances he/she will also consider your products. Hence, ability to influence downstream decisions for procuring products and services decreases in the latter phases of any initiative.
Successful execution. Strong PMO (Project Management Office) capabilities such as methodology, certifications, track record, etc and ultimately successful product/project delivery are key to application vendor success.
Service-oriented architecture (SOA). Large enterprise IT, convinced that no single off-the-shelf solution suite is ever good enough for them, are seriously considering component (services) based architectures, which is causing vendors to move into dynamic (or otherwise known as composite) apps middleware and services to prevent marginalization.