Zakk Wylde recently twatted on Twitter that he and Ozzy are back together after a few misunderstandings or whatever.

"Hey Berserkers, everything is great with Ozzy/Dad. See you at the Blizzcon convention in Anaheim August 22nd or before with BLS"

We reported first that Zakk was a bit upset that Ozzy had hired songwriters instead of using Zakk's material. articleWe find out that the reason Ozzy may have hired songwriters was because he was sure his music was starting to sound like BLS. (article)

Well things are apparently back to normal in Ozz at least until August 22nd when Ozzy won't really need Zakk to play guitar.