Unfortunately, only a small hand full of games utilizing the GCN-GBA connectivity were realized with Nintendo's vision of the concept. Titles like LotZ: Four Swords Adventure, LotZ: Wind Waker, FF: Crystal Chronicles, and the Splinter Cell trilogy for example (although Ubisoft screwed us by not including at least splitscreen multi-player modes let alone LAN) were amazing, IMO.
The problem was how expensive it got to fully take advantage of it. It wasn't convenient or affordable. A lot of people passed it off as a stupid gimmick, but what's funny (or disturbing) is that the majority of people I've spoken to who feel that way haven't even tried it. I totally recommend it if you have the extra money to spend. It really is a hoot, lol.
Now with the type of wireless technology for Wii and DS, it will be far more user friendly, convenient and affordable. I personally think Nintendo is on to something big, but the limitation of technology this past generation hindered it greatly. That and the lack of intelligent utilization of the concept by most devs. Only time will tell if the connectivity concept will take off now that the technology available has streamlined the experience.
Chance favors the prepared mind.