Some Frontier player usage numbers....
Pulled from the in-game Frontier leaderboards.... on the eve of the Fusion release, it seemed like a good time to report them, for fun and discussion:
388415 have medalled in the first Tier1 track (ie started the game)
122143 have medalled in the first Tier2 track (ie started Tier 2)
1345 have medalled in last "easy" Tier2 track (Spinners Alley)
440 have medalled in Hilltop Ghetto (technically, the last Tier 2 track of Beta)
25549 had ANBA long enough to get to medalled in Serpent Slough (last visible track for ANBA swamp)
532 have medalled in Steam Quarter (and are presumably waiting on the Maurader pieces)
248 have medalled in the 1st tier3 track (somehow got last 2 Riptide pieces and made it to Tier 3)
138 have medalled in Casino Rooftop (last? Tier1 track from slot machine)
13 have medalled in Balance Avenue (last? Tier2 track from slot machine)
0 have medalled in The Pendulum (first/only Tier 3 track from slot machine)