What is the difference between spells and spell-like abilities?

[pabelfly]

Likewise, utterances are SLAs with a specific exception to the “no verbal components” part: utterances all require verbal components.

The really interesting question centers around whether game elements that apply to spells apply to SLAs, what with that “just like spells” language floating around. That gets really ambiguous and potentially weird no matter which interpretation you use.

Yeah, was hoping for that to be cleared up. Looks like WOTC had as little idea about this as I do.