I advised about 3 or 4 people in the last week to buy Nikon, and it really hurt! I still love my Canon gear, but Canon left a deep scar with the delays of the 1D X, the delays in the 5D III and now the EOS 650.
Why did it hurt? Brand loyalty won't improve anyone's photographs. On the other hand I would say there is no clear winner between the 650D and the D3200. The D3200 has more pixels and better DR (the standard 'Nikon advantage' these days) but just 1 of its 11 AF points is a cross-type versus all 9 of the Canon's. Plus a flippy-outy screen and pseudo-video autofocus might be important to a beginner.
Maybe in future you could forego any sense of guilt by telling them that the two/three/four obvious choices are the 650D, D3200 and whatever else, and that they should go to a camera store who will allow them to play with each of these cameras for a bit, to see what fits them best. For a newbie the feel of a camera will be more important than the megapixels or dynamic range - and they might just prefer shooting with the Pentax after all.
Indeed, especially since the Pentax will have good image stabilization built into the camera.... I was a complete and clueless novice when I bought my first dslr a couple of years ago, a Nikon D3100, but fairly quickly switched to a Pentax K-5 and, a year after that to a Canon 5DII (plus a Rebel t3i as backup) - each better than its predecessor, and not just because I've become less clueless along the way.
So I still have a pretty good memory of what it's like to be a complete novice and despite that don't really know what I would recommend if someone asked me. If I knew for sure that they wouldn't want to upgrade to FF and wouldn't ever want to spend a lot of money on lenses, no matter how good they were, it would be easy enough to recommend Pentax. But it's almost impossible to predict such things - you don't really know until you get into it how much you might like doing low light photography (if you came from a point-and-shoot, how would you?), whether the effects obtainable via shallow depth of field appeals, or how far in you'll want to zoom, etc. So it makes sense to buy into a brand that gives a lot of options, both its own and third-party (Sigma & Tamron make far more lenses for Canon & Nikon than they do for other brands, DxO has proportionately far more modules for lenses that fit Canon & Nikon cameras, etc. ).
Between Canon & Nikon it could well be a toss-up (if I could afford it, I would probably want both). At any rate, it's not clear to me that a 3200 is a better place to start than a Rebel; a newbie who doesn't care about ISO etc. will likely care even less about dynamic range, especially the relatively slight differences in question and especially if he ends up knowing how to get exposure right in the first place (I don't know about the 3200, but my Rebel does that better as a matter of course than my 3100 did (as does the 5DII, of course)). But he might care that, like other low-end Nikons, the auto-focus won't work on some otherwise appealing Nikon lenses, whereas all Canon EF-S and EF lenses will work just fine on a Rebel.... (And he might, if he reads enough reviews, conclude that the D3200 isn't a better camera, period.) In any event, given all the Canons I see around the necks of tourists every day (they seem to outnumber Nikons), Canon seems to be doing rather well among newbies (yes, I know, that's hardly a scientific observation).
Ultimately I don't think it matters much. If a newbie likes the camera he buys and doesn't really get into photography, he'll be happy with what he bought and stick with it; after all, the differences among photos taken with any of the cameras under consideration will be pretty trivial to the non-obsessive, and the standard is very high. And if he does turn into an obsessive for whom these differences turn out to be important, it still doesn't matter much if he decides he should have bought into the other brand because - as I have found out twice - jumping ship isn't really that expensive. Unless he bought the latest camera body at its highest price, chances are he can sell what he initially bought for almost as much as he paid for it; any "loss" can be justified because he will nevertheless have taken some good photos and learned a lot in the process.