A few days ago, in Hyan v. Hummer, the 9th Circuit once again clarified how federal anti-SLAPP practice differs from California anti-SLAPP practice regarding appealability. In California, of course, an order granting or denying an anti-SLAPP motion is appealable. But in the 9th Circuit, the denial of an anti-SLAPP motion is appealable under the collateral order doctrine; but the granting of an anti-SLAPP motion is not appealable. For that, you need a true final judgment.
[6/22 update: See in today's DJ Jens Koepke's article Anti-SLAPP Appealability Getting Complicated]
Americans Love Litigation! Need proof? How about this here:
"This appeal began as a dispute between a landlord and a tenant over a $5 fee. Once the dispute entered the administrative arena, it grew to $9,932.87. After an administrative appeal and mandate proceedings in the superior court, the dispute is now here."