Watching the latest blocks fly in, 0.25-0.5% of the total block reward appears to be coming from fees recently. That's what miners are including; it may not be all the fees out there (there could be some huge transactions sitting around in mempool that just aren't deemed worth it).

In absolute terms, that's about 0.1BTC per block.

I consider that a large amount of revenue, because mining profit is marginal - analogy, a store increasing the price of its' widgets by 1%, assuming sales stay the same, will likely increase profits by far more than 1%.

The question is whether or not that inclusion influences block orphan rate enough for it to remain positive EV to include transactions. I believe it does (I don't think mining pools are generally benevolent).