Having played TF2 for 5+ years I've been involved in my fair share of debates as to what maps are the "best", "most popular" and so forth. I finally got around to looking at some data.
Here's a graph of the top 20 most played maps on Australian servers for the period 26 November 2012 to 3 December 2012. There's nothing special about this period, I simply picked a roughly 7 day period to look at. This data includes only normal TF2 servers - specifically it excludes MvM and all mods that I know of (such as PropHunt, Dodgeball etc).
The full list of (144!) maps is public.
Firstly - over a 7 day period Aussies racked up an astounding 4.4 million minutes of TF2. We played 8.36 years worth of TF2 in one week. Wowsers. And again - this doesn't include MvM, mods, idle & achievement servers etc - this is purely normal PvP TF2.
Given the number of 24x7 2Forts, Dustbowl, Turbine, Goldrush and Badwater servers it's unsurprising that these are the top 5 most played maps. It is staggering though that 2Forts, Dustbowl and Turbine make up almost 55% of the total play time.
I've never understood the popularity of 2Forts but clearly there is an extremely dedicated sub-population of the Aus TF2 community that enjoys it. Goldrush and Badwater often make up the core of popular fixed rotation servers and clearly that role is well deserved.
After that there's a few surprising results, at least to me. I would not have expected DeGroot Keep to be up in #6 – though we should note the clear gap between Badwater at #5 (6.7%) and DeGroot at #6 with less than half that (2.3%).
I'm surprised to see Egypt and Hightower up so high - I rarely see these maps played but that is the whole point of this analysis – it's clear that our own play style preferences bias our perspective on what maps are the most popular.
Doomsday is another surprise at #10 - most folks I know don't seem to like it but again that goes to show the bias inherent in one's group of friends. KOTH Kong King is also more popular than I expected – of all the KOTH maps I would've thought it's the worst hehe.
Double Cross is lower down than expected given that it's regularly voted in on full rotation servers I've frequented, and that there are a few 24x7 servers around.
As with all stats, the more you look the more questions you have. I'd love to understand the diversity of players across these map types – is there a distinct set of 2Forts devotees? – and are there specific factors that make the top 5 so much more popular than the rest of the maps?
Are these results surprising to you?
Methodology: I poll every server in Australia roughly every 5 minutes so we'll miss things like players leaving/joining between each reading but given that we are looking at total play time over 7 days these factors should even out and the relative values should be about right.