If I understand the rules correctly, the only levels that contribute to a familiar's abilities are Wizard and Sorcerer levels. Prestige Classes that increase arcane spellcasting don't do anything for familiars: one of the tradeoffs for multiclassing into the PrC.
Since PrC's have become so prevalent, there are few characters that don't pick up one or two (unless the DM bans them from the game). As such, it would seem like most arcane spellcasting characters wouldn't bother with familiars because they don't improve with their levels, and so aren't really worth thinking about.
Is there a single PrC out there that specifies it continues a familiar's advancement? How do you handle familiar advancement in your games? Heck, might as well add another one: how common are familiars in your games?
Since PrC's have become so prevalent, there are few characters that don't pick up one or two (unless the DM bans them from the game). As such, it would seem like most arcane spellcasting characters wouldn't bother with familiars because they don't improve with their levels, and so aren't really worth thinking about.
Is there a single PrC out there that specifies it continues a familiar's advancement? How do you handle familiar advancement in your games? Heck, might as well add another one: how common are familiars in your games?