Li Shenron said:
The metamagic rod FAQ is the most irritating. Either these rod work like Hypersmurf explained, or otherwise they should work really "on the fly" for everyone, and should not increase Sorcerer's casting time.
This is funny.
If it had stated that it did not increase the Sorcerer's time, everyone would be yelling that the FAQ was changing the rules again.
A sorcerer still must take a full-round action when using a metamagic rod, just as if using a metamagic feat he possesses.
The FAQ is consistent here. It states that it is on the fly for everyone and it takes into account this sentence.
As for Hyp's other interpretation, I can understand where he got it from. Hyp is very particular with language, hence, "use-activated" should mean the normal time metamagic is prepared for casters who prepare spells.
Having said that, I think the designer intent all along is for metamagic rods to be used spontaneously by all casters:
All the rods described here are use-activated (but casting spells in a threatened area still draws an attack of opportunity).
The word "casting" in this sentence has to be referring to the "use-activated". Otherwise, this sentence would not be here, it would be next to the one where it discusses Sorcerers casting spontaneously since Wizards would not be using the Rod while casting, they would be using the rod while preparing spells.
Hence, I think Hyp's interpretation is not correct based on designer intent. Context is sometimes as important as individual words when determining interpretation.
In this regard, I think the FAQ got this one correct based on original designer intent.
However, having said that, I also think that Wizards and Clerics should use metamagic rods during preparation. Using them spontaneously is too potent of an ability. IMO.