With Oracle’s recent purchase of Sleepycat, developer of the Berkeley DB engine used with MySQL, and last year of InnoDB, MySQL is left without a transactional database engine. MySQL supports plugable engines for it’s file storage, and the two that support transactions and the typical ACID properties have both been bought by Oracle. The remaining engines such as MyISAM do not support transactions.
Long term what does this mean for MySQL? The MySQL user conference is in April this year, so it will be interesting to hear from the source what the long term strategy is for the product.