Interested in coming back

Hi. I may be looking to return to the game after quite a long time, I used to be pretty good, played comp,was in a team for a bit. But this was when I was a lot younger. Last time I logged in was about 6 months before they rolled out Contracts for the first time, I tried to come back then but didn't

So I want to know, What has changed in that time,I've watched a few recent videos to try and catch up and I know there was a photo update more recently. (As recent as updates for TF2 gets).

Also what the hell happened to the economy!! One key is worth like 45 ref! It used to be like 5 when I played and traded last!!!