Yes i am experienced enough to copy a backup in no time and yes i have daily backups.
He asked a fair question and asked for opinions. I write software fairly often, and bugs do happen. We have about 30 site under daily management and we upgraded the first today. It was not easy. In the past year we have had one site hack for 30 sites. The time it took us put back a backup: 1 hour (because of the large number of files, if we had been able to upload a tar it would have been 15 minutes). The total time we spend updating joomla... i don't even want to know

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Most users have loads of components installed. Unless you have a perfect local test setup, testing joomla with all your components if difficult. So just 'risk' updating and hope every component still works? There is a chance you'll be searching for little bugs all day long (as i have today).
Somebody ones said: If it aint broken don't fix it. Cobal is a very old programmers language, but large systems still run on it. Thats not because its perfect, thats because it works.
Is it anoying when your site is hacked: yes. If you don't want to risk it: update. If you ask for my opinion on updating: i'll give it. If you want to start building a new site (from scratch): use the latest version of Joomla. (opensef/joomfish/search don't mix

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Hackwar i don't want to step on your toes and i can't expect a joomla test team to test a new version with all the components out there. I

Joomla! and it developers. I liked the opensef/MS way of doing update things. Release a public beta and let people test it with all their weird setups. There is always a group of early adapters which find most of the weird bugs (and their solutions). The less experianced user can wait until the final update appears.