Yeah, you're right. The leap from GBA to DS was bigger than that, but the two systems are still very similar, and many changes veren't that big of a jump, like the graphics.i'm just gonna point out why you're wrong right here.
comparing the DS to a GBA is a fool's errand. the obvious difference is the inclusion of a second screen. another large thing to note is the game media. the DS uses a slim card as opposed to a game pak.
on top of this, the DS had built-in wireless and wi-fi. the GBA did not.
what you want to say, is saying the game boy color/game boy advance is a glorified game boy pocket/game boy color. the game boy advance was an upgrade to the game boy color, moreso than the 3ds was an upgrade to the ds, but it was a large upgrade nonetheless.
the game boy color was an improvement to the game boy color, but it was still essentially a glorified game boy.
the 3ds added: gyro controls, a slightly larger screen, a 3d top screen, some improved software which allowed wireless communications to be better, an analog stick, and the improvements to the dsi.
everything else is virtually game boy pocket/game boy to game boy color. at most, game boy advance.
the 3ds is a glorified ds, though it does have a lot of improvements. it just doesn't have enough to warrant being considered an entirely new, fresh, innovative console. i has 3d, and it's improved under the hood. not saying other consoles don't do the same thing, just saying the 3ds is doing it, too.
Anyway, look at some of the quality 3DS games released so far and the ones that have yet to come out, and tell me that isn't a huge leap from the DS. Yeah, the overall design is very similar, and not everything about the system has changed drastically, but it's much more than just a glorified DS. The DSi is a glorified DS. If you think the 3DS truly is just a glorified 3DS, what do you expect from it to not be such? Of course Nintendo's going to keep the dual screens and touch screen, removing those would be going back a step. Expecting something that's radically different from Nintendo's best selling system of all time is crazy.