I wonder how much time will nexus 6 get updates. is it a good purchase? will there be an update for android 7? is it an end-of-life product?
Quoted from the link in @Firelord 's comment above:
Nexus devices get Android version updates for at least 2 years from when the device became available on the Google Store.
Be it the release date or the Store date, N6 still hasn't reached 2 years yet, so rest assured it will receive N, though not with priority, since Google takes care of their latest devices first.
Also, although Google makes the promise stating 2 years, that usually expands longer. Nexus 4 received 5.1 and Nexus 5 received 6.0 officially, making them ~3 years, and both keep getting security patches up till today. Nexus 7 (2013) got N Developer Preview which also counts to ~3 years.
Finally, there's always custom ROMs to get you covered. Not guaranteed to work 100% perfect as Google's stock, but as time goes and bugs get squashed, they approach 90%~99% if you ask me.
According to the image site for nexus it doesnt have 7.0 id say the N6 is done. but if you bought it and put cyanogenmod on it you'd get 7.0 and probably 8.0 , its still a good phone but after 2 years companys just stop updating