There's no real way to measure adoption, it's not something which (at least I think) you can measure through some stats such as the amount of TX's, google trends, amount of wallets, etc. The only sort of way of measuring this in my mind is to see if companies near you, or at least online companies, are accepting Bitcoin as a payment method. This, alongside more and more companies striving towards adoptiong Bitcoin as a payment method. That's the only way to get the consumers involved, as they don't care they just want to save a couple of bucks. If Bitcoin can do it, they'll use it -- if the dollar of a credit card does it, then they'll follow that.
a little bit of everything, do not trust one source
Meh, there's not TOO many sources on something like this. And even if there is, they usually follow the wrong data.
