Because you want to use something that it provides that 5.8 doesn't. Otherwise, upgrading for the sake of upgrading is stupid and foolhardy and shouldn't be done.
My criteria for good software:
  1. Does it work?
  2. Can someone else come in, make a change, and be reasonably certain no bugs were introduced?

In reply to Re: Why should I use perl 5.10? by dragonchild
in thread Why should I use perl 5.10? by saintmike

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