It gets lots of small updates periodically and I notice that this thing stays buttery smooth no matter what I do, and multitasking is quite impressive hardly ever reloading any app or webpage. The big screen is nice especially for typing and media consumption. My nexus 5 also runs super fast and even smoother actually so I have no doubt that the 6 will remain a fast lag free experience for a long while.
I did try the Moto X pure from Amazon, and it is going back. It's nice and all but I just do not see how it is a better device than the nexus 6 unless you absolutely must have the Moto active display features, and it is more expensive to boot. I did like the screen better on the Pure since the whites are noticeably more white and with constant onscreen buttons there is less chance of burn in. The Xperia is also an lcd, and my iPad is as well so yes the whites on the nexus 6 are more yellowish especially at lower brightness but it makes up for it with much much deeper blacks and insane contrast levels. Especially good for reading. Thus it doesn't bother me one bit because looking at it on its own the whites still look good.
The negatives are battery life, I get 4 hours SOT sometimes a little less and sometimes a little more, but right around there. The Pure got me 3 to 3 and a half with the exact same usage. Standby time also better on the 6. The other negative is the size, I thought the Pure was much more gripable and its so much more narrower that it feels so nice in the hand. I also thought that 5.7 vs 5.95 in screen size isn't a very big difference I thought the screen would be noticeably smaller but that wasn't really the case.
That was a long winded way of saying yes the nexus 6 is still an awesome device and will be for a while
*apologies for any grammatical errors, iOS9 killed my iPad Air. Keyboard lag is real