That would still presumably end up being Black Ops 3 though, at least from a consumer perspective, no?
I mean, if I had to pick something as the biggest seller guaranteed to release this year, CoD still seems like the safe bet.
I believe they're using the term based on momentum and sales and critical success combined from a single developer.
Uncharted 4 is coming off the high of TLOU sales and critical success and is the latest instalment in a franchise that I belive saw consistent growth (I.e. U3 outsold U2 outsold U1).
Uncharted 4 is launching on this gens most critically and sales successful console and so far I believe early signs are most PS4 franchise instalments are outselling their PS3 counterparts.
In short right now everything is positive about U4. It should be best selling entry in franchise yet and it could be at least well reviewed as U2 going off TLOU.
COD will outsell it but critically tends to be be below it and recent entries have been dipping below previous in sales hence their is a sense of CoD perhaps slipping past its peak.
Halo 5 could outsell Uncharted but it's coming off Halo 4 which is viewed now as a bit of a disappointment generally and there is a sense of caution on whether Halo 5 delivers.
In terms of the sum of its parts this year I can see how U4 could be viewed as "biggest release" in terms of expectations and the overwhelming sense of optimism surrounding the title.
Finally, Looking at ND trajectory with TLOU and current PS4 momentum we're in a market place where it's possible Uncharted could outsell Halo. I reckon Halo 5 will still outsell it but the fact it's not a foregone conclusion indicates the combined momentum of PS4 and ND have right now.
Pure sales wise sure a new CoD entry should still deliver but after two current gen entries it's obvious hype and market interest is fairly average - it's just another CoD in a sense.
After Unity AC feels tainted too as a franchise and again interest in new AC feels more muted - oh another AC, wonder if this will be a good one or a bad one.
Despite the vocal minority overal feel for Uncharted and ND is clearly overwhelmingly positive.