Certainly Bananagrams is the closest thing to a popular fad "board" game to come out in a few years.
There's an interesting Boston Globe profile of the game and it's Rhode Island designer here.
I got to try it recently and I have to say I was pleasantly surprised. Like many truly classic ideas, it's so simple you have to wonder why nobody came up with the idea before. The basic idea behind the game is to form crossword-style anagrams based on speed, rather than maximized points as per the game Scrabble.
It's really pretty clever and a lot of fun. It comes in a banana-shaped pouch and has144 plastic letter tiles. Player's start with a specified number of tiles and try to use them all to form words, crossword style. The first player who does says "peel" which forces everybody to draw a new tile. Players continue, and every time a player succeeds in using all the tiles they call out "peel" again until there are fewer tiles left than players in the game. Whichever player succeeds in using all his tiles at that point calls out "bananas" and wins.
This reminds a lot of the old Avalon Hill game Tuf-Abet. In that game players rolled dice with letters on their faces. Each player had his own set of 20 cubes of different colors. They used the letters to form crossword-style letter groups. The first player who used all (or most) of his cubes said "Tuf" which started a 3-minute timer where the other players tried to outdo the first player in how many cuibes they used. If someone did then they said "Tuffer" and started a 2-minute timer where everybody tried again to outdo the others. A third round and any subsequent "Tuffest" rounds are 1-minute long. Play continues until somebody uses all their cubes. The winner is determined by a point scoring system that rewards being the first declarer, the final declarer and the number of cubes used, with a bonus for words over 5 letters long.
Interestingly, game documentation included in my copy of Tuf-Abet from 1969 indicates that a patent was applied for. If a patent was ever granted, it is long since expired, as patents are only good for 20 years or less. The Banagram site makes no patent claims, only copyright. The Boston Globe article and the Banagram Web site both mention Scrabble as an inspiration and have no mention of tuf-abet but the designer is certainly old enough to have come across Tuf-Abet in his lifetime, so I wonder if the resemblance between the two games is entirely coincidental.
There don't seem to be any intellectual property problems. As I noted, any patent is long-since expired and there seem to be no copyright or trademark issues either. What is fascinating is how two rather similar games have had such a different reception. Tuf-Abet was never a big breakway hit for Avalon Hill, although it seems to have been a steady seller. Bananagrams is Game of the Year. Bananagrams has a very clever marketing hook, while effective marketing always seemed to be a weakness for the old AH. Tuf-Abet's scoring system and multi-round format is a little more intricate than Bananagrams, but it's still not very complicated by either 1969 or contemporary standards. Perhaps, if Hasbro still has the rights from its AH acquisition, we might see a reprint of the game, given the success of Bananagrams.
I've always liked Tuf-Abet, although I haven't had much success in getting people to play it over the years. While there are similarities, I do think Bananagrams is the better implementation of the idea. By dispensing with any kind of scoring system and going with a simple win-lose game condition the newer game is probably more accessible for a mass market that considers games like Monopoly, Scrabble and Risk as pretty complicated.