I am not sure DBA skills are necessary. You might be thinking, "Um, you are a DBA and your livelihood depends upon it!" Let me explain.
DBAs are necessary so long you own a RDBMS. Does this mean you need a full-time DBA? No, but you will at some point need the skills a DBA has. Many times a DBA is called in after the developers who built the system are all out of ideas on how to fix it. Developers are seen by the unknowing as THE all knowing entities. They make shiny new applications that enable me to click a button and have the world succumb to my will. The problem is this lumps all parts of the application under their domain: front-end, middle tier, back-end.
Most developers have learned enough about those three tiers to glue together the application and get it to work if only in a POC. Management signs-off on this and it heads over to production where the real trouble starts. I truly believe this is where the NOSQL movement was born.
I try to keep up with NO-SQL, the technologies and concepts and I keep seeing on common thread. It's all about the developer. This frees whomever is using this technology from needing the skills of a DBA. No tuning of your IO system, physical layout, logical layout, or complex queries. Just through more hardware at the problem (Scale Out). It's interesting to note that has been the mindset of management for a long time with RDBMS, but they couldn't understand why it wouldn't always solve the problem.
DBAs are specialists, like cardiologist or anesthesiologists. You have no use for them until something goes wrong. DBA skills are only necessary when you have a system that uses them. In this tug-of-war with NOSQL, we shall see just how much we are needed in the future.