IGN has given 29 games a 10/10 in its history, while Gamespot has given only 8. Out of those 8, 5 of them were also given a 10 by IGN:

1.The Legend of Zelda: Ocarina of Time (1998)

2.Soulcalibur (1999)

3.Grand Theft Auto IV (2008)

4.Metal Gear Solid 4: Guns of the Patriots (2008)

5.Super Mario Galaxy 2 (2010)

So, which game do you think will be next, if any? Do any of the currently announced games have a shot at becoming game #6?

Hopefully Zelda U, but that won't come from Gamespot if there's no VA. IGN is more forgiving.

Hard to tell with these guys since they don't seem to have a specific pattern. But I guess MGS V PP would be the safest bet

I'd say MGSV has the best probably.

I think Uncharted 4 has a good shot.

I think zelda U and Uncharted are good calls, but it may not happen this year.

If Bloodborne also feels better than the past Soul games, it could happen too.

Goddamn GTAIV got a 10 from both of them. Should we care which one is next? Nope.

GTA VI, of course ^^

GTA IV...Jesus Christ that is incredible. That game bored me to death lol.

OT most likely Witcher 3/Uncharted 4/Batman

This is my vote also and  I also agree GTA IV was boring as fuck.