There is a very non-factual rumor, with very little current backing, that when Google does search updates, it first updates the mobile phone index, the one that iPhone, Android and Palm OS uses, and then the main desktop index. I don’t think they have different indexes for mobile phones to access versus desktops to access – but it is possible they show a fresher Google data center to mobile users or test things out first on mobile users.

Again, this is all early speculation, that even if true, could have happened once and could never happen again. Here is the first post from WebmasterWorld with this discussion:

Senior member, whitenight, said he was considering the same thing but didn’t want to say anything yet. While administrator, Roger, found the theory to be “interesting.”

Forum discussion at WebmasterWorld.