Xenoblade Chronicles first released back in 2010 before being brought to Europe and the US in 2011 and 2012 respectively. Very quickly the game went out of print, in the US especially, and became incredibly expensive in retail. The game was then ported to the New 3DS a few months ago that helped, but now the original is coming to the European eShop for Wii U.
Nintendo of Europe sent out a press release this morning to promote the release of Xenoblade Chronicles on the Wii U eShop. This is not just a mere announcement of a future release, but rather the reveal that the game is available already on the eShop.
Even better, those who buy the game on the eShop will be eligible for a discount on the upcoming Xenoblade Chronicles X later this year. When that game launches in December, as long as you buy it within the first two weeks of release and previously bought Xenoblade Chronicles for Wii on the eShop, you will get discount of £9.00 GBP.
The version on New 3DS is definitely fine for a handheld, but the Wii version is vastly superior graphically and if it is available, is definitely worth the purchase.
While this has released in Europe now, a US release is still not a certainty, at least very soon. The US has lagged behind terribly on Wii games on the eShop behind especially Europe and also Japan, so it might be awhile.