I agree with previous posters. The market seems to be going mostly Oracle and SQL Server. So many applications come with SQL Server or Oracle as the preferred backend database that it is almost impossible to avoid them. That should lead to plenty of SQL Server jobs in most companies. Tough to avoid Microsoft these days.

I had this decision to make back in 2003. I had the option of becoming a dual DBA in SQL Server and Oracle or I could focus on becoming an expert in SQL Server by doing more projects with Analysis Services. I decided to specialize in SQL Server and I have never looked back.

You can either be average at both or really good at one.

From the DBA perspective, I think the products are simply too huge to be an expert at both Oracle and SQL Server.

From the developer perspective, you can do both.