Total Fail... spin off would be the kiss of death.
So lets be clear. VMWare is a core component of Pivotal which is EMC's 'Green Stack'.
So it would mean spinning off Pivotal from EMC, where Pivotal is a separately run company already.
Take out VMWare, you weaken the stack and you end up losing money.
Spin off Pivotal, and you have even less of a reason to look at it compared to the other Hadoop distros.
(Not that anyone is taking Pivotal seriously... )