Tetris is eternal, if you just let yourself run it, you are immediately into it again, it's such a game, and Peggle is in that category. Although there is significant difference between the two. Tetris is mostly about speed, fingers speed and decision making speed, and in that we reach limit sooner or later and aren't improving after that, at least that's what happens to most people, while Peggle seemingly being much more random, is actually a lot about skill of judging geometry and recoil. I found that there is no limit in improving your skill with Peggle, only improvement is not as fast, but it's there. It's probably possible to get so good at it, that you can clear stages with moving hard objects in several hits if you play long enough (><)
Rubick's Cube was awesome idea, there is no denying that, but people get bored by it pretty quickly, once you put it several times, there is no meaning in playing further. Still a great toy. I can see how it can be improved though, although such improvements would make it much less appealing, I must admit.
I think everything has a certain threshold of repetition and peoples' tolerances vary depending upon their preferences. I sure couldn't play Minecraft as much as some do (plus I see those Yogcast folks about town from time to time) but other are besotted by it.
Though I know even in 10, 20 even 30 years time if I'm still kicking about I could easily pick up vanilla Tetris and still have a blast. Though not Tetris Blast though. That's one of things I was trying to say that I can see Peggle 2 trying and just like the additions of the 4x4x4 and 6x6x6 Rubrik's cubes, it's a reiteration of a great idea that loses some of the originals charm and magic.