Hey, I can do that.
Lizards New Super Improved SRD-Based Game
Dispel Magic: This dispels magic.
Fireball: This creates a ball of fire.
Fly: The caster can fly!
Invisibility: The caster can turn himself or someone else invisible.
There you go. The DM decides any specifics or answers any questions. After all, we don't want to slow the game down with lots of fiddly rules.
More seriously, I think this is another example of how constrained the 'design space' of 4e is getting, and how fewer and fewer truly different effects/concepts/etc can be wedged into it. It looks like almost anything interesting is being dumped into a huge bin labelled 'rituals'; virtually all spells/powers/exploits are simplistic variations on a few themes, with complex concepts like 'mirror image' becoming just a special effect for 'ablative AC buff', for example. You can no longer bring down a flying mage with dispel magic (always fun!), remove a ward/sigil, turn off that annoying magic sword, etc.