Yeah, ipad 3 will slow 3DS down, maybe kill Vita, if not Ipad 4 next year will be the final nail in that coffin.

Not at $600.
The people who buy a 3DS or Vita are in a completely different class than those who will buy an iPad.

You know people say $250 for Vita is too much......

I can imagine the iPad hurting the dedicated handhelds, but not killing them. Handhelds have not focused on the Flash-like style of game since the Game Boy, and that is the bread and butter of iOS devices. Unless you're seriously suggesting that people are buying the 3DS for DSiWare and the Vita for PS Minis, I doubt there's much overlap.

It sure would be foolish to dismiss Apple's newest device and think it won't affect both the 3DS and Vita.  In my opinion, because of the release date, price and features it is more of a threat to Sony's newest hardware than it is to Nintendo.  However, it will still adversely affect BOTH the 3DS and Vita (moreso the latter) especially if rumours of a budget tablet priced around $249-$299 are true (making it better bang for the buck compared to Sony's beautiful machine).

Yes, but when Apple releases an iPad mini or reduces the price of it's iPad2 to combat budget Android devices and gadgets like 3DS and Vita it is inevitable that it will impact the dedicated portable videogame system.  It's a lot less childish to many mainstream gamers to game on an iPad than it is to game on a Vita and 3DS and that is the stigma Vita and 3DS has.  Again this article is pretty insightful:

http://www.industrygamers.com/news/ipad-3-vs-ps-vita/

because the iphone 4s really slowed down the 3ds sales right? You guys have been saying this thing for the last 3 years.

Can you play Mario, Zelda, Pokemon, Mario Kart, Uncharted on the IPad3? No?
Case Closed.

Here is where I show you Mario Kart for iphone (It is ripoff game), and here is where I should Uncharted (ripoff game), but I am to lazy to look them up. Pretty sure I can get Zelda clone as well, Pokemon Yellow Fake is also on the iphone, and really Mario.....would be surprised if no one ripped him of. 

and they suck and have no name recignition(which is 95% of it)

Right, but are they more than superficial clones?