Both Switch Models top 20 for the first time in ages! What I like to see!

Damn, Switch software is just dominating the Amazon charts.

"But ports don't sell consoles"

Lol.

It varies, but Ubisoft hinted back in early 2016 (when XB1 was more competitive than it is now)
that pr user amount, XB1 had a 1.25 attach rate advantage vs the PS4 (for ubisoft titles in 2015-2016?).

I dont think thats the case today tbh, and again it varies greatly title by title.
Some games see like 90% of their sales on PS4 vs 10% on xb1 (like Monster Hunter World)

However even if you "said" the avg xbox gamer buys 25% more mix of software/microtransactions, the fact that theres like 40m+ more PS4's out there than XB1's, means overall total software on PS4 is going to dwarf the XB1 sales.

http://www.vgchartz.com/yearly/2018/Global/

Well Ubisoft has done bundles and marketing partnerships with Xbox in the past.  I would say in general, attach rates for PS4 and Xbone are probably fairly similar since a lot of games perform markedly worse on Xbox One in terms of sales vs PS4.  However, as PS4 continues to pull away, that will change a bit.  Also some things are skewed by the uneven distribution of Xbone's userbase vs the market.  PS4 has a big presence in three regions.  Xbone has a big presence in the US, an ok presence in Europe, and no presence in Japan.  So attach rates for games that do particularly well in the States but falter elsewhere could well be higher for Xbone due to that imbalance.  But the opposite will be true for Japanese games as a big part of the potential audience is not there at all. 

My math has it at 6.4 games for each Xbox and 6.5 for each ps4.

Smash bros just refuses to leave the top 5!
I wonder if its gonna become a trend where the kind of big Switch titles go out of stock ahead of release, at least on amazon.

After almost 1 month Bayonetta 2 is in the edge of the chartz. Is it any normal? is it a good or bad sign? Let me know vgcharters.

Neon Switch, being only available to Prime members, has caused Grey Switch to shoot up to #15. Is this a sneaky tactic from Amazon to move more stock of the less popular model? Lol

Nintendo games usually stick around for longer in the charts so that's not good news.