In light of stompix's thread, the cumulative amount of fees in these last blocks is extremely similar to that of the difference in the block reward, as we all know, being halved in April.

This could be a test by miners themselves to create a benchmark, the benchmark being how much network activity is required in order to achieve the difference in block rewards

Why?

In the past, the block reward was the primary revenue for miners. As BTC was distributed and as time passes, the network needed a benchmark of activity in order to ensure that there would be an incentive to secure the network in the future.

As we have moved in time, the block reward has been sufficient, and miners have been able to move the market in their favor to ensure mining is profitable (as long as activity trajectory mentioned above is suitable, which thankfully, has been!)

Now, moving the market requires liquidity that miners may not have, same with purchasing power. It's more about fees, and so, measurements must be made. This might be what we're seeing.

I wonder how this will effect the halving as we know it....