Apple has not told us the resolution of the 
Watch, except it's a Retina Display.
Just snapped two watch face pictures from Apple website (really hard to download pictures from the newly designed Apple website, anyone?)
http://www.apple.com/watch/gallery/
With the clear board of the display, it's obvious the display is not square.
Initially I thought it might be 3:4, but after cropping out other stuff, I got two pictures with the resolution of 202x253 and 210x262, which both have the aspect ratio of 4:5.
With the Retina Display, I think the resolution would be 320x400 for the 1.5" version with about 342 ppi, a little above the 326 ppi of the 4.7" iPhone 6.
As for the 1.65" one(which is 1.1x the size of the 1.5" version)
a)if it also houses 320x400 display, the screen density would be about 310 ppi, which I think maybe a little bit not enough.
b)if it also comes with the same 342 ppi, the res would be 352x440, that's just 21% more pixels than the 1.5". Also, it seems the display is OLED, cause Apple says it's "extremely energy efficient" (see screenshot below from http://www.apple.com/watch/technology/). I think with a bigger chassis and hopefully a bigger battery (remember, display is not the only component that burns batt), it's definitely doable with the extra 21% pixels.
So
320x400 for the 1.5"
352x440 for the 1.65"
Watch, except it's a Retina Display.Just snapped two watch face pictures from Apple website (really hard to download pictures from the newly designed Apple website, anyone?)
http://www.apple.com/watch/gallery/
With the clear board of the display, it's obvious the display is not square.
Initially I thought it might be 3:4, but after cropping out other stuff, I got two pictures with the resolution of 202x253 and 210x262, which both have the aspect ratio of 4:5.
With the Retina Display, I think the resolution would be 320x400 for the 1.5" version with about 342 ppi, a little above the 326 ppi of the 4.7" iPhone 6.
As for the 1.65" one(which is 1.1x the size of the 1.5" version)
a)if it also houses 320x400 display, the screen density would be about 310 ppi, which I think maybe a little bit not enough.
b)if it also comes with the same 342 ppi, the res would be 352x440, that's just 21% more pixels than the 1.5". Also, it seems the display is OLED, cause Apple says it's "extremely energy efficient" (see screenshot below from http://www.apple.com/watch/technology/). I think with a bigger chassis and hopefully a bigger battery (remember, display is not the only component that burns batt), it's definitely doable with the extra 21% pixels.
So
320x400 for the 1.5"
352x440 for the 1.65"