Well, it seems many have put up their wishlist for features they would like to see in MySQL so here is my list. These are in no particular order of importance, just as they came to mind :)
1. Online Backup - This is currently being developed and it will make a big difference to many people currently trying to administrate MySQL. We can only hope that it gets done soon and is well tested to avoid any major issues.
2. Standardised HA/Replication - Along similar lines to the consistent online backup is that of consistent high availability, load balancing and replication. No matter what the engine being used, this will allow a consistent method of implementing these features regardless.