Good news: As you read this, you can very soon start downloading the first version of MySQL 5.5 from http://dev.mysql.com/downloads/.

Some things are the same as before, others are different. Let’s start by looking at the version string, SELECT VERSION();

mysql> SELECT VERSION();
+--------------+
| version()    |
+--------------+
| 5.5.0-m2-log |
+--------------+
1 row in set (0.00 sec)
mysql>

And let’s look at the highlights of the release notes, or better still, MySQL 5.5 in a nutshell in the manual on http://dev.mysql.com/doc/refman/5.5/en/mysql-nutshell.html. Top of the list is …

With all due respect to Monty (and I mean that — much respect is due), I have some serious issues with his portrayal of the 5.1 release.  I hate to make my first entry on Planet MySQL about a controversy, but he encouraged people to blog about their experience with 5.1, so that’s what I’ll do here.

Overall Quality

As a long time user, I am very confident that the quality of 5.1 GA far exceeds that of the initial 5.0 GA release (5.0.15).  In fact, I would go further and suggest that the MySQL organization has if anything been too conservative about declaring 5.1 GA.

It’s obviously true that there are still many bugs open.  However no software is bug free, especially not those with codebase as large as MySQL.  So the question is not if they are bug free, but are the …