Spellbooks are fun. They exist in fantasy literature, they add to that whole wizard library archetype.
I suggest that instead of the 3E incarnation of an item that essentially contains your character's abilities, spellbooks should be magic items. Each spell in a spellbook can be cast as a ritual (casting time measured in minutes). The book itself provides some of the power for the spell. Once cast, that spell can't be cast again for X days. So essentially, a spellbook is like a collection of scrolls that never burn out.
This change puts a wizard's class abilities where they belong--with the wizard himself--while encouraging a wizard to find and keep spells. It also introduces the fun fantasy trope of coming upon an obstacle, and the wizard then pores over his various books for the right spell (which then takes several minutes to actually cast).
Components are also fun, and flavorful. In my opinion, the common practice of handwaving the wizard's bottomless component pouch is no better or worse than the common practice of handwaving the archer's bottomless arrow quiver. I suggest that most core wizard arcane abilities (careful not to use the word "spell", there*) shouldn't require components. However, certain spells should require components. Those components should be tracked as diligently as arrows are tracked.
And I'm totally in favor of a wand or staff being a "focus" needed for certain spells or abilities, much like the cleric's holy symbol.
-z
* I think it'd be cool if spells in 4E were like a fighter's sword: a tool that can be used with proper training, but is essentially external to the character. Arcane abilities would be more like the fighter's swordarm/Str bonus; an internal power able to be used at will. It may be too subtle a distinction, but hey that's my wishlist.
