I dunno about that. They've done it with every previously unannounced newcomer so far, so it might just be a spoiler warning/joke about new characters. Your interpretation is possible, but I wouldn't go and call it certain.

They had the warning banner with with the Pokemon dude too, right?

Yoshi's been associated with dragons, but I think it's become less over time. I know in Super Mario World that the 5 large coins you'd collect in each level for a 1-up were called Dragon Coins, and they had Yoshi's face on them.

Maybe we can just call him a dinodragon, or a dragonsaur.

This is actually pretty cool. Yoshi is sort of my 2nd or 3rd favourite after Ness and Luigi so this is really sweet. I predict a stage tomorrow or an item.

 Good point.  I'm glad someone else commented on that topic.  Apparently though Sakurai thinks it is a big enough debate to model Yoshi's character this way.  Sure it resembles traits from Super Mario World.  Hm.  wow.  Nintendo must have MEANT for him to be a dragon!  I mean think about it.  Nintendo is a japanese company, Yoshi has a long neck and they make him have Wings, Breath Fire, Pound the Ground, Eat things with a long tongue.  Wow.  Maybe Miyamoto and Nintendo was shocked that everyone thought of him as a dinosaur here and that is why he brings up the confusion so blatantly in this post though we thought it obvious.  As a Dragon, this smash makes much more sense.

There were several reasons that people thought of him as a dinosaur though, first as I mentioned the scientific mentality of the western world, then the fact that there were other Dinosaur creatures in Super Mario World that gamer had also never seen before that games release, his resemblance to a Tyrannosaurus, and the fact that at the time the Super Mario Brothers movie, which sucked, made him look like a dinosaur. 

 Well if he is going to do doubt updates occasionally like this, then that throws everything out the window.

He's doing big updates this week because of the GC convention.

Yeah, maybe because of the convention we'll get a second character tonight. That would be awesome. I love these updates!

I love these updates too... but if metaknight doesn't come soon i'm going to lock myself in a closet. Or maybe not...

And Ganondorf was confirmed before right? because he was my favorite "evil" character in Smash. I hope they give him a whole new moveset. Assuming that they do, he'd probably be announced much later.

One of the main guys behind the Zelda series has said he submitted character designs for Ganondorf and Sheik to the Brawl team, but that doesn't mean they're 100% certainly playable, or even in the game. I would expect Ganondorf to be playable and Sheik to appear as an assit trophy, although Twilight Princess Zelda turning into Sheik wouldn't be that bad.

Now if only they'd have Ganondorf like he was in the final boss battle of Twilight Princess...

The reason we got two is becuase it's Kazumi Tokata's Birthday. He is the voice of Yoshi and K.K. Slider, and well as does the music for both.