I should be getting the DK game at some point because I purchased Professor Layton on the eShop right after Christmas. Honestly though, I don't really care. I didn't buy Layton that way BECAUSE of the DK game, I bought it because I feel that type of game lends itself to being accessible very quickly on the system memory rather than having to swap out a cartridge. The DK game is just a little bonus - that I'll probably play once and then hide it in a folder.
Also, I second getting Donkey Kong '94. Such a great game which also inspired the equally great Mario vs. Donkey Kong series (though I wish the series would someday return to its original gameplay instead of always using the Minis…).
Meanwhile in Europe… *sigh @ NOA*