Sellers are now asking for 2 keys, and none of them is selling at anywhere close to a key. However, all those that are asking for 2 keys are unsold, and the buyers seem only willing to pay ~1.5.

Unsold for around 2 keys:

http://www.tf2outpost.com/trade/6790832 - Selling for 2 keys

http://www.tf2outpost.com/trade/6894632 - Selling for 2 keys

http://www.tf2outpost.com/trade/6914044 - Selling for 2 keys

http://www.tf2outpost.com/trade/6894160 - Selling for 2 keys

http://www.tf2outpost.com/trade/6904482 - Selling for 4.66 ref

http://www.tf2outpost.com/trade/6615967 - Selling for 2 keys, offer of 1 key + 1.33

http://www.tf2outpost.com/trade/6787488 - Selling for 2 key

Only ones sold on OP, these trades average out at around a key and 1.33:

http://www.tf2outpost.com/trade/6851063 - Sold for a key + a ref

http://www.tf2outpost.com/trade/6497518 - 'considering offer' of a key + 1.33

http://www.tf2outpost.com/trade/6743514 - Sold for a key + 1.66

http://www.tf2outpost.com/trade/6264894 - Sold for a key + 1.33

This shows that 1.5 keys is both the maximum that buyers are willing to pay, and the minimum price which sellers wish to sell for, thereby making it the price.

And for once guys, don't be mystery down voters. On almost all my suggestions there are ~5 people who down vote without posting a comment. If you have a valid reason why this shouldn't go through, tell me! Others can follow your lead - if you're right.

Let me know what you think :D