Yes, this seems to be the case. I am pulling the trigger on white 770s today.
The problem of comfort and longeivity of 770s ( and any future model JVC will pack in the same cup/enclosure/design that first appeared as HA-M750 ) is interrelated.
The linkages that allow for folding do not allow swiveling of the earcup - and if your skull bone structure does not fit the angles for HA-M759/HA-S770/etc exactly, you will expirience some sore point or sore line after wearing those for say more than half an hour. Depending on your skull form, it can be either the line in front of your ear or behind it. The steel headband is quite strong - perhaps you could try to bend/deform it a bit to adress this problem.
As a consequence, plastic linkage pieces ( besides your skull ... ) are in such a case overstressed - and will fail eventually, as my HA-M750s did. Armed with this hard learned knowledge, the incoming 770s will get steel band "custom bending" and plastic linkage reinforcement - prior to any listening.
Circumaural design of 750/770 should be much better than anything possible with HA-S500.
Things we do for sound ...lol !
for those wondering about the hs-770, check out their thread as one head fi member got one already
here is the initial description: Soundwise... interesting out of the box they don’t sound like the S500 at all. Less bass, less highs, good mids, and a more natural tone. Are these midcentric headphones? Too soon to tell, but it looks like it.