Before Worlds last year only Miranda was seen flying a bit. Then at Worlds the triple K 'Danger Zone' list brought in TLT tactician Wardens which have since been seen popping up a lot in Store Champs list. And a 4 Warden list with autoblaster turrets won a Store Champs somewhere. Last weekend I won a store tournament (8 people) with 3 Wardens with seismics and Conners.
When K-Wings were announced and released, I don't remember there being this much excitement and now they are appearing everywhere with success.
On a power creep note, compare the Warden with the Contracted Scout. For only 2 points more the Scout gets an extra agility for those 9 health points (but does give up half health).