The Open Solutions Alliance (OSA) just published the results of the 5 customer forums they held in 2007. The report is a quick read (11 pages), and is quite thoughtful and balanced. I will highlight a couple of points I found particularly interesting, but I'd encourage you to read it for yourself.
First, a great insight from the report is the relative popularity of Postgres for serious applications. Customers in the forums were from "both public and private sectors, both large and small organizations, both business and technical managers, and both early adopters and mainstream users. When asked about their open source usage, "about 50% used open-source databases, equally divided between MySQL and Postgres." Equally divided...hmmm...
If measured by pure downloads, MySQL's claim of being the world's most popular database is certainly true. But most serious developers know that Postgres (particularly that slick distribution from EnterpriseDB ;-) is the world's most advanced open source database, and that it combines extraordinary capability with terrific ease of use.
Another great insight from the report is the question of why people gravitate to open source software. Cost Reduction is "by far" the number one reason, particularly because it allows you to pay later in the usage cycle, when the code's value is delivered, rather than paying up-front licensing. Just as important an insight is that the Ability to Customize code is not at all important; most people want their software "as is."
These two points precisely reflect our experience with our customers. They are looking for less expensive alternatives that are available for free until value is delivered. Furthermore, customers want to know that experts are building their software, and have little or no interest in modifying the database code themselves. There are, of course, exceptions, but they are few and far between.
There's lots more meat in the report. Go read it!