If you look at the progress of open source products you can gradually see a complete software stack coming in to place. However, a quick analysis will reveal that there are currently many gaps in the stack (as there are in every software stack) – most of them are happily filled with good proprietary products. The pressure that open source is putting on the market is gradually becoming clear. Open source products can and do establish themselves in areas where products have tended to become commoditised and not much further innovation can be expected. This is where open source eventually wins hands down. Open source can establish itself in other areas, if it gets solid backing from a major vendor – but the vendor has to find a viable revenue stream as IBM has with Apache and Linux and CA is attempting to do with Ingres.