So it's not hard to understand why they want to discontinue one of them ...
About Google Page CreatorOk, that's great, but right now Google is doing a "MobileMess". They're replacing one incomplete solution with an even less complete solution.
... We are no longer accepting new sign-ups for Page Creator because we have shifted our focus to developing Google Sites, which offers many of the capabilities of Page Creator along with new features like site-level navigation, site-level headers, control over who can see and edit your site, and rich embeddings like calendars, videos, and Google docs.
If you are currently a Page Creator user, you can continue to use Page Creator and your pages will automatically be transitioned to Google Sites later this year...
Sure, Sites can embed gadgets -- but I haven't been able to make good use of their other supposed advantages. In particular the "file management" is not a significant improvement over Page Creator's very feeble solution (if you control your domain you can create a Page Creator/domain solution that works pretty well, but that's another topic).
On the other hand Sites pages look awful in Safari/iPhone. Ok, so they look lousy anywhere -- can't Google hire some graphics designers? Still, they're worse than lousy on the iPhone. On any browser the Sites "footer" dynamically expands (why?!), but on the iPhone this tricks Safari/iPhone into filling most of the half-VGA screen with an ugly, empty, footer.
There are other issues with Sites -- though Google is slowly chipping away at some of them. Maybe in a year or two Sites will be an adequate replacement for Page Creator.
It's not ready now.
Learn from Apple's foot-shooting blunders Google. Don't migrate until Sites is ready.
 Page Creator, Sites, Blogger, Presentation, Spreadsheet, Docs