Wait man.

Or he could wait for the inevitable price drop

It's really a great system so Go get a Wii u now

You could wait to buy the console but buy the games you are interested in now. They will not be cheaper in the future, some will even be more expensive as second hand games!
If Pokémon is your main interest you should, as mentioned before, buy a 2DS/3DS.

You also have to consider the fact that you will become part of the Nintendo Family and how that influences your reputation!

Buy now. The entire library is available now. Join a discount club like Best Buys gamer club. 20% off all games adds up fast.

Yeah, but I would advise to buy the games you want now as they may still be available and therefore cheaper, games are now becoming hard to find, if the NX is BC (which I doubt) then you can still use the games 

The best answer to this question is to wait to see if the NX is BC with the Wii U. If it is then wait unless their is a huge Wii U price drop or you find a good deal on one. If there won't be BC then buy one if there are games you want to play on it. By now its worth the purchase if you like Nintendo games.

I advice you to wait and see if the NX will be backwards compatible with the WiiU games. If it's not then you can buy a WiiU.

It's almost guaranteed the NX isn't BC now

100% wait, i meen, at least till nintendo officially unveals the NX