nah here is the compare the s3 version that is using sony imx175 camera sensor

sensor type	sony exmor r	foveon sensor
size	1/1.32" [0.76" diagonal]	1/1.3 [0.77" diagonal]
pixel unit size	1.75	2
total magapixel	8	4
processing chip	samsung	imagechip 2
stabilization	sony steady-shot[digital]	optical stabilization[lens type]
HDR video	No	Yes

Source from Wired -

"We took the HTC One out to a dimly-lit restaurant and it produced far better, and cleaner, images that the Samsung Galaxy SIII we had with us. The HTC One’s photos were much clearer, and you could plainly see everyone in them. Photos snapped with the Galaxy’s 8MP camera didn’t look any sharper than the One’s 4MP images. The only advantage to the Samsung’s snapshots was you could zoom in tighter on a subject’s dark face."

MP is smartphone world is irrelevant... it is the sensor that counts and the chip / software processing
you can take sony 12mp pic and compared to S3 8MP and the 12mp will still lose in pic quality
the race is on for the best 2013 flagship phone
hope this phone have no iphong scuffgate with the aluminium body

spec sheet trumps the best 2013 phone so far Xperia Z
and if it manage to start shipping soon enough and make it available earlier than Z, it will eat into the XZ market

if u c sensor size & pixel size, htc have the advantages, in basic explanation
since bigger sensor size by 0.01" and able to capture more light by 0.25 microns
so u will notice a more detail & brighter photos

but the downsize is the sharpness, bcauz of 8mp & 4mp
8mp*1.75 microns is more thn 4mp*2 microns, thus resulting samsung s3 photo will be sharper

thn to the feature of HTC one, optical stabilization is better thn the digital
thus resulting a more stable grab whn shooting.

thn HDR video which provide a balance exposure between bright n dark area
example of HDR video does

Two different models.
One smaller and better performance.
Another one a tad bigger screen, splash proof and have micro sdcard slot. Just pick whichever one that suits your need and fancy...lolz

Wooo..and the phone will cost a bomb..!!