FYI, I've had some really bad problems crop up when using sym links to deploy php releases (php selectively using files from older versions), and I've encountered others who've had similar problems. I don't know if it's been fixed in newer versions, but problems include the realpath cache not getting properly reset (and clearstatcache() wouldn't let you clear the realpath cache until 5.3).<p>Here's someone else who had this problem, although he claims cycling Apache would fix it (it didn't for me):<p><a href="http://www.mikebrittain.com/blog/2009/05/12/case-against-using-symlinks-for-code-promotion/" rel="nofollow">http://www.mikebrittain.com/blog/2009/05/12/case-against-usi...</a>
Question for the peanut gallery: how do you handle user uploaded files that are not in version control if you swap out the whole site?<p>Create post-update, pre-swap symlinks from inside the new docroot to directories outside of the swapped docroot?