If none of that freaks you out, then I have one word for you: Oracle.
This to me smacks of FUD.
Oracle, evil and terrible as they are, would have a very hard time killing or otherwise harming MySQL due to the code being GPL'd and the vibrant MySQL community (Percona, Facebook, Twitter, Drizzle, MariaDB, SkySQL, etc) that fixes bugs, adds features, and directly competes with the work Oracle does.
At the same time - changing data values not stupid? We may differ on this point but I believe it's insanity. I'd love to see NULLs honored as well as constraints.
Finally, it's easy to characterize my comment as FUD but Oracle has a habit of using Open Source systems to its advantage. Why else would they buy MySQL? And the licensing is not as strong as you may think.
Either way - it's very argumentative and I'm happy to agree it's unsure at best.
To compete with Microsoft SQL Server and to further solidify their customer base (most Oracle customers already use MySQL).
Here's one word: upsell _HARD_
That was my experience trying to buy support/license for GlassFish. Some sales guy tries very hard to upsell us to use WebLogic (of course, otherwise he's not going to fill his quota or get a bonus).
There is NO evidence that MySQL has licensing problems otherwise we wouldn't have the Facebook, Twitter and Percona forks. It's as simple as that really.