My brother bought the first Xenoblade Chronicles with that £8.99 eShop deal the other day. IMO, I recommend playing it first since the newer game is updated, looks better and has various improvements. It's tougher to go back to the original when it doesn't have as many features/look as good.
Fun fact, the awesome Xenoblade Chronicles X soundtrack is done by Hiroyuki Sawano and his team, who did the soundtrack for Guilty Crown (an anime I've never watched, but I've had the sweet soundtrack for a long time). Unfortunately there's no word on a Western release for this OST, despite the fact that the vocals only seem to be in Western languages including English and German. So one might have to resort to 'shadyness' to obtain it.
My order of the LE from French Amazon said it won't be arriving on time for tomorrow, it says 5th-7th Dec. I don't mind, more time for the first Xenoblade Chronicles I guess.