As most of you know, Sun acquired MySQL (and later Oracle acquired Sun), and during these acquisitions, there were a lot of FUD in MySQL community which resulted in creation of
If you're upgrading your databases anyway, you should consider other FOSS DBMSes, or data management software systems as well, not just MySQL.
For example, if your DB workload is analytics more than transactions, and data is mostly added in batches, you should consider using MonetDB, a columnar DBMSes which is about 1.5-2 orders of magnitude faster than MySQL when doing analytics-only.
Another option is PostgreSQL. It's more transaction-oriented - like MySQL; in fact, they're similar enough to be proper competitors. There are arguments for preferring PostgreSQL and arguments for preferring a MySQL variant.
On DB-engines.com you can find other potentially-relevant DBMSes, FOSS and closed-source/commercial.