Not in person. I have looked at the specs and compared them with the 70D -
http://bobatkins.com/photography/digital/canon_eos_80D.html - noting the differences and improvements.
Looks to me like the biggest difference for the average shooter in normal operation would be the larger number of AF zones. Personally, 95% of the time I use the center AF zone. I don't think I ever let the camera pick the AF zone. However some people use the outer zones and they can be helpful in tracking a moving subject, so I can see an increased number of zones being useful for them.
The larger number of pixels (24 vs 20MP) really isn't likely to result in a noticable difference. The ISO range is pretty much the same so I don't expect to see much difference in noise and DR. The 80D does add 60fps 1080p video and a headphone jack for monitoring audio, so for videographers those features might be of use. I don't shoot video, so they don't matter to me.
Overall the 80D is a nice incremental upgrade to the 70D, but the difference really isn't enough to make
me think about upgrading (and I have a 6D and 7D, so I really don't need yet
another DSLR!). If they had given it AF at f8 and changed the sensor design to significantly increase DR and reduce noise and maybe going from 20MP to 30+ MP I'd have considered upgrading. However if that ever happens it will probably take at least 1 or 2 more upgrade cycles to get there.
I'm pretty happy with my 70D and not looking to upgrade. However if I had a Rebel or a 60D or earlier EOS DSLR I'd be looking at the 80D as the best mid-range, mid-priced upgrade. For those looking for a bargain, the 70D price might drop significantly now that it's no longer in production. However right now, the 80D at $1199 (
http://www.adorama.com/ICA80D.html?kbid=12417) looks like a better deal than the EOS 70D at $999 (
http://www.adorama.com/ICA70D.html), though you can get an "open box" 70D for $799 (
http://www.adorama.com/ICA70DOB.html).