Pikmin 3 is used to refer to the next, as of yet untitled, game in the Pikmin series, which was announced during E3 2008[1].
Past hints
Around the time of the release of the first Pikmin game, it was hinted at that Pikmin may be a trilogy.citations needed
On July 30th, 2003, Pikmin's creator, Shigeru Miyamoto, said in an interview with Gamers Mark that he had already got the basic idea for Pikmin 3 in his mind.[2]
On 21st April, 2006, Spong news asserted that according to its press contacts Pikmin 3 would appear on the Wii at some point, probably some time after the launch[3]:
From what we can gather from our press colleagues, Pikmin Revolution is a cert, though its showing at E3 cannot be confirmed.
On 12th July, 2007, in an interview with Shigeru Miyamoto, an IGN interviewer asked if he planned to do anything with balls. His reply was as follows:[4]
I certainly don't think we've seen the last of Pikmin. I definitely would like to do something with them, and I think the Wii interface in particular is very well suited to that franchise.
On the 18th of April, 2008, Shigeru Miyamoto revealed in an interview on the topic of Wii Fit that he desired to continue with the Pikmin series:[5]
As for what the developer would like to work on next, Miyamoto said he's looking forward to working on the Wii some more. He also reiterated his desire to make another entry in the Pikmin series of action strategy games.
On the 15th of July, 2008, during E3, Shigeru Miyamoto answered questions about a possible Pikmin 3:[6]
There isn't anything that we can announce right now, but I’m sure we’ll probably do something with it. The Pikmin team is, of course, still there and maybe we’ll have something to talk about before too long.
During E3 2008, Shigeru Miyamoto said, when asked about the Pikmin series, "We're making Pikmin." Nothing else about the Pikmin game in development was revealed, however.[7]
On July 24 2008, Shigeru Miyamoto said this in a interview: "...They (the Nintendo development teams) are all working on new Mario, Zelda and Pikmin projects"
Olimar in SSBB
The appearance of Olimar in Super Smash Bros. Brawl for the Wii was widely considered to be an indication of the likelihood of a third Pikmin game being released.