I updated the OP with current numbers. Thanks to the VGC-team for fixing the problem hindering new data and get the numbers flowing again. I think you usually get too less credit for the work you do for keeping the site running.
This week was interesting, because it saw many new releases. In difference to the past, this consisted of releases head-to-head instead of late ports. So the first week data is actually more interesting. The games in question are the Street Fighter Anniversary Collection, Harvest Moon, Owlboy, BlazBlue Cross Tag Battle, The Liar Princess and the Blind Prince and Sega Genesis Classics. Aside from Street Fighter sadly the games all missing at least one platform. Sega Genesis Classics aren't coming to the Switch, the others not to the Xbox. Of the games only Street Fighter broke 100K, although the sales indicate that Harvest Moon should get there soon, and BlazBlue so far only released in Japan, the releases in the other regions should improve sales too.
This are the market shares for the games:
As you can see, the performance strongly differs from game to game. Street Fighter dominates on PS4, is strong on Switch and weak on Xbox. We have so far few data for fighting games among all three platforms, but this collection also thrives on nostalgia, so it is hard to conclude how the sales are influenced by these factors. BlazBlue gives some indication for fighting games, but keep in mind this so far is only japanese data and missing the Xbox. BlazBlue though shows a strong dominance for PS4 with nearly three fourths of the sales on that platform. Sega Genesis Classics can indicate nostalgia sales, but this is missing Switch. Here PS4 dominates even stronger with more than three fourths of the share.
Harvest Moon is interesting, as we have so far few games with the simulation genre among these platforms. No Xbox-release though only let's draw conclusions for PS4 and Switch. Here Switch takes the cake, with more than 70% of the share.
Owlboy once again shows the sales strength of Switch for Indies and platformers. Over 80% of the sales are going to the Switch.
The Liar Princess and the Blind Prince is a port of the Vita-game. As a japanese-oriented game it misses the Xbox. As many other games it shows that for publishers PS4 and Switch start to replace the Vita as the platform for japanese centric story driven games. The sales are interestingly very balanced between PS4 and Switch, nearly identical.
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I added a new graph to the OP. This shows how many games on each platform are selling more than 10%/20%/30... market share. It shows a bit the PS4-domincance in sales. I'll keep that updated in the future.
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I also want to show another interesting development in sales. The game BattleChasers: Nightwar (a pretty classic turn-based RPG) was released as a late port on Switch and shows there incredible sales strength. I think THQ Nordic is kinda pleased with these sales. In three weeks the Switch version already overtook the XBox One version and if the strong sales continue will not take long to catch the PS4 version.
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