I've been on WoT since October 2014. It's now late January 2015 and I'm starting to get good in Tier 2, including playing against Tier 3 tanks. I've been a Wikipedia editor for years, so I hope I can help here, too.
March 2015: mostly upgraded to Tier 3, starting to get some decent matches.
December 2015: mostly tiers 4 & 5, a few "home-grown" tier 6s and some specials. Solidly potato, which isn't great but it's not terrible.
March 2019: mostly Tiers 5-8. I have one "home grown" tech tree Tier 8, the others are purchased.