This is a very true point.Quote:
Can get messy if you leave 5.5 to default to innodb as some scripts don't define the storage engine in their mysql create statements. You'll be getting alot of support tickets asking how to convert innodb tables back to myisam ! Unless, you're prepared to also provide optimisation and tuning advice for innodb related options and performance tuning. As well guides on how to properly backup innodb databases and repair/recovery of corrupted innodb tables and proper handling of innodb shared table space (ibdata1).
Average joe ain't up to speed on innodb vs myisam differences, so enabling 5.5 to default to innodb storage engine may get messy. Safer method would be to set mysql 5.5 to default to myisam via my.cnf options above. And let those that understand innodb enable it themselves.