Is there a schedule for google updates of any kind? I have been updating my site content, keywords, submitting directories to increase my backlinks, etc. I'm curious when I might see some changes in my page performance.
My sarcastic sides says. "Is there one?" Truely the answer is only Google knows. Generally visible pagerank has been updating every three to four months, backlinks every month to six weeks but anything can happen at any time.
No, google updates when it feels like, though you can see past updates here, http://www.ebusiness-strategies.co.uk/newsGoogleDanceupdates.htm
I don't think there is any schedule for Google updates including PR, Backlinks, Directory, & SERPs. Anything could happen at any time.
Google updates continuously, a process called "everflux". Periodically, the data is exported to Toolbar PR, etc. Matt Cutt's Blog: What's an update?
"Estimations" and "Predictions" are pointless. It will happen when it happens. You can do just as good a job as those endless mindless "prediction" tables by spitting into the wind and seeing where it lands. Or flipping a coin 20-30 times, turning around three times, clickng your heels together, and throwing a dart at a calendar (or do best of 3 or best of 7 if you prefer, perhaps calculating the harmonic mean of all the dates the darts hit).
Yes, you can never predict google updates, I remember when it used to be pretty much monthly, PR and IBLs, nowadays it's more like every three months, though as Minstrel says it's 'actually' updating constantly, you'll see the effects of SEO in the SERPS before anything is confirmed by an update. Guessing when an update happens won't do you any good, only constant SEO will.