So…
Should I jump the gun and head on to MySQL ver 5.0? 
Normally, If I still had the old system’s administrator hat on from my previous job I would download it immediately into a test server for tinkering… a few weeks sniffing the forums for bug reports… then do some more serious tests with existing applications… if everything is in order, schedule the upgrade of the DB… of course we have to simulate the upgrading in another server just incase there might be a hitch… not to mention the much needed back-ups of the previous DB that is oh so career saving whenever Murphy’s Law decides to prove it’s existence… *snicker*
What I like about ver 5.0 is the production implementation of the much awaited Stored procedures and triggers… a lot can be said about the convenience/peace of mind that these features bring to a database… not to mention to an enterprise system… single point of change, security of code, reduced network traffic, event driven code (triggers), faster transaction time… combine that with the existing transaction safe features of INNODB tables… you have a serious combination for use in a production environment…
Which of course impacts the bottom line… why would you want to spend gazillions on a commercial RDBMS if you can have on for free?… hey just don’t forget to buy the tech support… I wonder how the stored procedures will fare with their commercial counterparts in terms of speed? 
that is of course what we’re after in the long run… aside from the bottomline of course… *snicker*