I haven't substantially worked with iPhone/iPod Touch, but as far as I can tell from others' evaluations, browsing is similar in speed on both platforms, but different in feel. The iStuff has somewhat more fluid scrolling and especially zooming, but the N8x0, while less fluid, needs much less scrolling and zooming, because it has 2.5x the pixels. Some people prefer one, some the other. (I, as you might guess, prefer the N8x0.) Trying them both before deciding is probably best; hope you can find one to try.

As for available applications, you can check out http://downloads.maemo.org for descriptions and screenshots of many (but not all) available apps. I'm not watching the edu-games market, but I have seen that there are some out there.