It is only Arcane Magic that will be affected by this, although there will probably be some similar changes for the Druid as well as Psion. Not really going to do the extra work if there are none in game though, so without further aduei...
Spells can be cast directly from the spellbook, if it is not one that was memorized at a penalty of time. Arcane casters must power the spell from within; so they would have to read the spell in order to attach power to the words, then recite it. For encounter spells the delay is 1d2 and for those more complex daily's 1d3, the score would relate to the delay it takes, getting a 1 will allow the PC to cast that spell next turn.
A scroll will still operate normally, as it draws its power from the words already written and only needs to be spoken.
CASTING ABOVE PC'S LEVEL
It will be possible to select one spell from ONE level above the PC's current level and cast that spell from the spellbook (with appropriate delay). The arcana table (which is forthcoming) will change to a difficult check if it is a daily, and a moderate check for encounter spells. casting a spell of your level and below will perform normally on an easy DC.
ARCANA CHECK TABLE
the DC check for 1-3rd level pc's would go something like this
- 15+ -normal
- 12-14 - random effect on target
- 10-11 - random target within 2 squares
- 8-9 - random target and effect on battlemap
- 7- spell fizzles out as it leaves PC's fingertips
RANDOM EFFECT TABLE (uses d6)
- 1 - fizzles out
- 2 - becomes a burst
- 3 - 1/2 as powerful
- 4 - normal
- 5 - random damage type
- 6 - 1.5x's more powerful (was going to do 2x's, but decided to leave that for the natural 20's)