This is a really naive WoW addon that will calculate an item's weighted score based on your current class and spec. It adds this score to item tooltips for ease of access. It literally does nothing more than this. It is currently only set to handle all Mage specs, all Rogue specs, and Windwalker Monks. I'll add the other class and spec combos as time goes on. This item score cannot replace common sense, thinking, simulations, etc...
The initial weights found in core.lua were obtained from IcyVeins class guides and other class and spec specific sources.
If someone finds this addon and decides to try using it, I recommend that they first run simulations on their character (in SimC or via AskMrRobot) to obtain their weighted stats.