I'm guessing they will be near clones.

In the picture with the Katrina sticker where the face sprites should be there appears to be a 'U'. What could it mean?

It could come from Unusable.

 That's what I think is happening too. 

I see Ness and Lucas as having Luigi and Mario thing, where they are very similar move sets with only a few differences between them.

Neither Lucas nor Ness gets PK Fire, Thunder, Starstorm, etc in their respective games. Most of their Earthbound/Mother3 powers are healing related, so I guess their current moves were borrowed from other characters in their games to flesh them out a bit. We don’t know Ness’ B moves yet, but I don’t see them changing much as every other returning character’s moves have stayed relatively the same. 

Otherwise the main differences seem to be in their smash attacks and the rope snake. In Mother 3 Lucas never uses a yo-yo which accounts for his different smash attacks, while Ness probably won’t get a chance to use the rope snake as it's exclusive to Mother 3.

why does there have to be a cap on the # of charaters... This will be the last SSB game in A VERY LONG TIME... I hope they made it possible to purchase charaters from new IP's they do not exist yet 3 years from now... that would so cool... imo the more the merrier, as long as we don't get clones again(I did not mind the clones, I just wished they had created new movesets for each)...

If they add Luigi I hope they add new moves or else he will just be another Mario.

^I'm sure Luigi will have his Poltergust 3000 from Luigi's Mansion.

will their be a mario w/ f.l.u.d.d. ?

Agreed.  I think Luigi will much more different from Mario than he was the past two games.  I do think Ness and Lucas will be very nearly identical though.  That's fine with me.  I don't mind one or two near-clones.  

^hopefully:)