Well.. have to say still at it and still grinding away and playing. Joined a clan and it has helped in the fun factor a LOT.. as seems to have taken the need to spend so much money down a bit. I have in about 3 weeks gotten to a AMX 12t (GOD the grind trough that HORRIBLE AMX 38 was killer), and a M41 Arty..
Overall spent a good bit over $100.. mainly to get a few bigger tanks to help jump XP.
That said, I have found even with buying some things, it only speeds up the game, it doesnt give me an advantage when playing lower tiers.
Maybe if you get into the Clan wars and have to buy gold ammo, etc.. it will be a P2W.. but after 3 weeks and about $29 or so a week (averaging 10-15 hours a week) I can honestly say if I didnt spend money I would be about half as far in the game, but tactically I wouldn't have gained anything on the people I play.
In casual gaming seems the matchmaking system pretty much balances the game play real well.. Cant speak for Clan Wars though as I haven't gotten that far yet.