@Jason Barnett.

Thank you so much for reading and commenting! I've been thinking of how to analyze data to glean predictors… I don't know if sales data will be enough to predict cards/decks prior to popularity, though with enough data, something might be possible. When looking for smaller and smaller spikes in sale, and not having access to all the singles sales out there, the false positives would probably be more frequent then the real indicators. I do think though that the more information and sources i feed into my calculations the better results i'm going to have. However, since this site is dedicated to the financial aspect of MTG deck trends may end up being a byproduct of what we are really looking to discover. The Demand Matrix will be expanded to cover other formats as well, but there is a lot more work I have to do on the spread sheets to make it useful. I'm also working on learning some other ways to crunch the data that is better suited to the task.

I have been wondering if we can use card sales as a predictor for cards / decks that will be popular for upcoming events. If you have the time it would be sweet to see a demand matrix for the pool of Legacy-legal cards over the last week or so and see how the data compares with Grand Prix Columbus deck choices.

At this time all my prerelease data is just copy/pasted from ebay.com sales and into excel to be manipulated. Additional information was gathered from TeraPeak.com.