WebmasterWorld administrator, Neil Marshall, posted a thread at WebmasterWorld saying he has noticed that Google's efforts to keep many data centers powering search in sync has been slow.
In short, he said that when Google updates, he is often seeing a longer lag time for all the other data centers to keep up with that change.
We all know that personalisation can make a big difference to what we see in Google SERPs, however, the data center updates can also make a significant difference to your traffic and site performance.
I used to see more frequent updates to the data centers, but, i'm surprised to note an apparent slowness for updates. For example, I think almost four weeks is a long time for the data to be refreshed, unless there's something else in play.
Of course, he didn't do any analysis, this is just his perception after watching Google's data centers for 10+ years. He gets the feeling that things have been slowing down. Maybe it is time for a new caffeine update from Google?
Pedro Dias from Google also noted something yesterday about it on Google+. He showed an example of when the data centers are not in sync:
Slower roll outs, slower updates, slower results? I am not 100% sure about that. Google is obsessed with speed.