If there's something new in 5.6 that you really need, switch. Otherwise, wait for 5.6.1 (which I've heard will be out soon enough).

In my case, I don't need the new features (lvalue subs, extra Unicode goodies, but the 'our' keyword would be nice), so I'm happy with 5.5.3.

On new ActiveState installations (on Windows for clients), I've used 5.6 (ActiveState 613 or something like that) with no heartache.