It integrates anything that can be represented as a number. Prices, number of badges, importance of titles, it doesn't matter. You can combine any of those inputs into a relevance formula that is evaluated at query time. Of course IndexTank won't find those inputs for you, you have to provide them.
Are the historical values of those signals kept and queryable? Such that I could check document ranking with signals X, Y and Z today and 3 days ago and check the impact of the signal changes?
