According to this article about the recent EU decision Microsoft and NetApp are competitors.
"The pact negotiated by the European competition commissioner, Neelie Kroes, and Steven Ballmer, Microsoft's chief executive, will enable Microsoft's competitors — from global enterprises such as IBM Corp., Sun Microsystems Inc. and Network Appliance Inc. to small, independent software developers — to make and sell server software that works seamlessly with Microsoft's, which industry experts predicted would open vast new sales opportunities."
But according to this article NetApp and Microsoft are partners.
“NetApp is proud to increase its commitment to Microsoft and the MTCs. Our increased investment in the MTC program demonstrates our current success and desire to serve customers using the Windows Server platform,” said Patrick Rogers, vice president of Products and Partners at Network Appliance."
This could be a case of keeping your "friends close and your enemies closer", or it could be the beginning salvo in a opening battle between the two companies. Either way, as a customer or competitor you have to wonder who is leading the PR campaigns in these companies because customers are receiving two very different versions of how these companies view each other.