Last gen DKCR, Demon's and Dark Souls are the closest to perfect 10 in my book.
This gen so far no game gets close to it. MGV could potentially have been a perfect 10 if boss fights weren't rubbish and if they managed to actually complete it before release.

Dragon age origins, finally passed it last week. Amazing game. Playing 2 and...it's decent I guess, but nothing compared to the original.

Xenoblade Chronicles.

I'm iffy on whether to give a 10 to Devil May Cry 3 or not. If not that, then Super Metroid, though boy that was a long time ago.

I would say that really no game has had the honor since Xenogears. That is imo the game closest to the perfect game for me.

I would say Xenoblade and the mass effect trilogy were the closest.

WiiWare version of Cave Story. Outside of that? I'm not sure any "new" or NEW game I've played in the last.....very long time, honestly deserves 10/10. There have been at least a few 9s. But 10? I dunno. There ARE 10s in my gaming past. But nothing recent.

The true and only game that has deserved the perfect score in modern times is Mario Galaxy 1 and 2 in my opinion.

The most recent 10/10 game I played is Batman Arkham City.

The Last of Us.

The last one I can think of was Undertale. That was really great and felt perfect for me, haha.