Recently two questions about chil(l)i got edited to the word with single letter L.
Is the US spelling preferred here and should be edited?
For tags, yes, though we should set up synonyms to handle multiple spellings if necessary.
For titles / bodies, it's not so crucial, so long as it's clear what the asker means. I would still recommend that we prefer US-english spelling just to make it easier to search, but it's not absolutely necessary - Google will figure it out even if our internal search doesn't.
That said, I approved one of those edits, because I honestly forgot about the double-L spelling and assumed (like the editor) that it was a typo. This... Will tend to happen. Don't get too concerned about it; if you want to roll it back, go ahead.