Sounds about right, if not even a little low. I remember PS4 and Xbox One shipped 4.2 and 3.9 million respectively over their first couple of months, though I don't quite remember how quickly each shipped 2 million. 

EDIT: Went back and looked it up. Yeah, ps4 shipped 2.1 million its first month, and then another 2.1 million its second. The Xbox must have done much the same, as it shipped 3.9 million by January 1st 2014, though it only sold 3 million. 

I expect the launch month to go very well, it´s the months after that will be telling.

Really will depend on launch line-up and price. But this can be said about any console. Hell, Wii was selling at 2x its price via eBay for over a year while WiiU was selling for 20% cheaper by January on eBay.

With what people like Emily and Kate have been saying on Twitter/blogs, I think it is certainly possible that:
1) NS will have very strong software line-up from Nintendo and 3rd parties.
2) NS price will be $250 to $300 allowing a solid launch price point for consumers.

Not really accurate according to what I read, the 4.2 millions number is for 2013. The PS4 was launched the 15th of November in the US and 29th in EU, and not launched in Japan before 2014. Your numbers surely mean 2.1 millions for the first 2 US weeks, and 2.1M more for the EU and December in the US, not exactly 2.1M a month (didn't the PS4 sell 2M in the first few days?). 

So 4.2 millions = 1 month EU + 1,5 months US, a lot closer to 1 month worlwide (maybe even less) than 2 months. 

EDIT: The PS4 sold 1M the first 24h in the US (and Canada), and more than 250k in the first 2 days in the UK. Pretty sure the 2M were sold in less than 48h if you align the different launches. 

Depends on launch line up, and i hope scalpers don't pre-order it.

Seriously, please let me buy Nintendo Switch. D:

 True, but since we don't know the specifics of the Switch's launch, it's a bit hard to compare. I was just saying that both Sony and Microsoft were able to push off about 2 million within a relatively quick time of the initial launch in the US, so Nintendo should be able to do around the same, not how much they'll be able to do afterwards :)

hmmm...That seems a little low for a console launch. I might have to preorder it then.

I agree. I did a quick edit of my previous post, the PS4 apparently even sold 2M in 48h if you align the different launches, and 2M more in the first month after that. 

But it was Christmas, there was a huge buzz and everyone needed to secure one for the presents. The Switch's launch will most likely be less crazy. 

Nintendo products will always sell out initially because there is a large hardcore fanbase for the company, their games and their products.

We will see in 2-3 years how well the console does and how third party developers support it, First thing I want to see is the official spec sheet and the battery life.

http://www.vgchartz.com/weekly/41609/Global/

Go look at 14th Dec 2013 (about a month after Launch).

the PS4 did ~3M  and the XB1 ~2.2M

Mind you these are units sold, not shipped.

So its "less" than what the XB1 or PS4 shipped by alot.