What I’d love to see in Piwik, either as a plugin (which I’d be happy to pitch in on) or integrated into core functionality, would be a trend line extrapolated from historical data to compare the current view to.
That’s a feature I became very familiar with in Omniture and it would be very, very helpful in Piwik.
So, for instance, yesterday I was looking at my current Visits total and noticed that it seemed a little high by 10 a.m. Right now, the graph only shows the total number of visits, and today is nearly always going to be below yesterday.
To see whether that put me on pace for a higher-than-usual day (it was) I went back and looked at the hourly reports for the previous four Tuesdays, added up the total through the 9:00 hour, averaged it and compared the figure.
I think a software-based trend line would be computationally fairly simple. It would be a fantastic addition to core functionality because a trend line or set of trend lines (“1 week average,” “1 month average,” “1 year average,” etc.) could be added to any graph and show where the current data point is. But even a dashboard widget that showed a prediction, based on the average of the last 4 XXXdays through that time period and over the whole 24 hours, would be an improvement over Excel.
I’m not familiar enough with how Piwik plugins work to make a significant contribution. But for my department’s internal use, I’ve started putting together a script from the API that will make a prediction for me that I can run at 10 a.m., 1 p.m. and 5 p.m. when I like to see how we’re doing. I’ll post here that once it’s functional.