Wizard Spellbook: Where is all the space?

[Psyren]

An open question to which I want to answer "yes," but can see arguments for "no," is whether a cantrip remains a cantrip when you apply metamagic to it. This is really only relevant to PF, not 3.5, but consider whether a enlarged mage hand can be cast at will, or consumes the 1st level spell slot in which it's prepared and thus cannot be cast again.

I bring this up because it seems pertinent to the "what level does the spell really count as?" discussion.

"In general, use the (normal, lower) spell level or the (higher) spell slot level, whichever is more of a disadvantage for the caster. The advantages of the metamagic feat are spelled out in the Benefits section of the feat, and the increased spell slot level is a disadvantage."

Using the higher slot is less advantageous (as now the number of casts are limited, and the metamagicked spell competes with higher level spells) so you are required to use that.