Full disclosure: I know the guys who made this. I won't compare it against the competitors since I haven't used alternatives but my 2 cents:
1) This has been years in the making--these guys have spent the last couple of years focused on making the best tool possible.. days nights and weekends!
2) They're super passionate about games/gamers.. they've organized gamejams and html5 meetups and are really in touch with the community. They're in this 100% and very open to feedback--so expect loads of improvements in the next couple of months!
I haven't used it, but I remember looking at the minified code a while back when it was first released. It looks very well done, by someone who has excellent game-engine design experience.
Developers behind the engine are actually have major experience in such companies as Activision, Sony, EA, Rebelion, and few others, so yeah, they know their stuff :)
THREE.js is very low-level framework, while PlayCanvas additionally to low-level engine access has game framework, which will allow you to create game logic and scripting in much better way.
1) This has been years in the making--these guys have spent the last couple of years focused on making the best tool possible.. days nights and weekends! 2) They're super passionate about games/gamers.. they've organized gamejams and html5 meetups and are really in touch with the community. They're in this 100% and very open to feedback--so expect loads of improvements in the next couple of months!