Harry Potter fan sites such as MuggleNet and The Leaky Cauldron have been spilling over with angry comments about Warner Bros.' decision to bump back the release date of "Harry Potter and the Half-Blood Prince," ABC News reported Tuesday.

"Totally disgusted by WB's decision," an unidentified user on MuggleNet wrote. "I'm totally convinced that the decision was motivated by money and only money." Meanwhile on Leaky Cauldron, another fan wrote, "This is a huge let down (sic). I can't believe that they are moving it back by nearly eight months!"

The network also said online petitions are making the rounds, demanding that the original release date be restored, while some fans say they are planning a protest outside Warner's New York headquarters.

"Like every other studio, we are still feeling the repercussions of the writers' strike, which impacted the readiness of scripts for other films," Alan Horn, president of Warner Bros., said in a statement released last week.