I've been pondering this for awhile, and I haven't really come to any conclusion. The original Super Mario Galaxy was arguably average in difficulty (not hard, but not easy either), and Nintendo has said that the next installment will be harder. From screenshots and videos I have seen, it doesn't seem any more difficult then the first one, and arguably looks easier.

So what do you think? Have faith that what Nintendo said is true, or expect similar difficulty as the original?

All of the impressions so far have said the game is harder than the original and that some levels were really challenging

Sorry, but to me it was very easy. The only time I died was because I was trying to skip over an enemy (was doing a speedrun) and I accidentally touched him and got pushed back and fell in some black hole... With that said, the low difficulty level didn't make the whole package bad, but it wasn't as memorable as the other games because of it me thinks. Only the soundtrack and atmosphere made it worthwhile IMO.

I really hope it's going to be harder, but that's because I like to think that what I'm doing in a game as a point in the end, to get to the credits and feel a great sense of accomplishment (believe it or not, some games even today can make me feel that way). Still, what can I say? Won't be able to comment on this until we get the game, no?

A few of the 120 stars in the original were hard - purple coins on luigi's face, and the purple coins on the battlerock I think (the moving platform one)

And yeah, the next is meant to be considerably harder, I expect they'll still make it so that pretty much everyone can get half the stars, then a steep curve after that

I hope it's easy to beat but hard to get 100%. Kids play Mario games, not just us old-school Mario fans. I don't want my kid getting frustrated because some 30-something gamer wants his game about princesses and dinosaurs to be soul-crushing.

I hope so, Miyamoto said it was.

I have two thoughts on the matter.

New Super Mario Bros Wii looks easy, but it does have it's hard spots. Watching someone almost always makes a game look easy.

3D platformers are easy. This is a fact of life. The reason is you typically are only threatened by missing a jump. Most bad guys can easily be avoided and they don't overload you with bad guys and platforms at the same time. In 2D platformers (like Mario anyways) they can put a lot of bullet bills, pits, and goombas and still have a challenging and enjoyable level.

that stage with the flipping platforms triggeres by Wiimote shake looks hard

EDIT: this is the one
 

these are some random (harder) levels from IGN:
 

i think it will be more difficult than the first one, but i have a feeling that Nintendo's definition of hard may not be what most people (at least non-casual players) think

Count me all the way out of the "galaxy was too easy" crowd...

I ran through it, it was awesome, I wouldn't have it any other way.  

Difficult = fun, is an outdated gaming principle.