At what point does "homage" become "outright Hamburglar-style theft"?

Fans of inoffensive acoustic singer-songwriters have found their loyalties divided this week, after listeners noticed that a line in Taylor Swift's song "All Too Well" (off her new album Red) sounded almost identical to one in singer Matt Nathanson's 2003 song "I Saw."

Here's the Taylor Swift line:

"And I forget about you long enough to forget why I needed to"

Here's Matt Nathanson's:

"And I'll forget about you long enough to forget why I need to"

If you've just gotta hear this poetry sung aloud, a post on ONTD notes that the Swift verse occurs at 2:13 - 2:24 here; the Nathanson one at 1:44-1:50 here.

Determining whether the line was bitten coincidentally, accidentally, or as an homage is tricky, particularly because Swift is a noted fan of Nathanson. She's even gone so far as to scrawl some of his lyrics down her arm before shows, I guess because that's a cool thing to do?

While many Swift fans are already protesting the former future Mrs. Conor Kennedy's innocence, Nathanson seems pretty convinced it was a straightforward rip-off.

Here's a tweet, apparently aimed at Swift, he posted a couple days ago after the rumors first surfaced (h/t ONTD):

While that tweet has since been deleted, a couple other ones taking swipes at Swift have since gone up. Here's a jab he retweeted the same day that was taken down:

And here's another posted Friday, just as the story is beginning to find a wider audience:

Nathanson also noted that "writing lyrics is like pooping [B]uicks," perhaps suggesting Taylor Swift has a real, real big butt and that's why she's so good at writing lyrics. (Or that writing lyrics is a difficult task which requires a lot of effort and concentration, so 1. it's bad to "borrow" them without credit 2. if you use someone else's lyric, you're pretty aware of it because that's not a Buick you pooped out yourself.)

While Swift has yet to make a comment on the matter, it does seem odd that someone whose reputation is built on writing her own lyrics and being raised by a family of daisies who always taught her to do the right thing would intentionally "steal" a lyric from a songwriter so famous he's got his own blue check on Twitter.

Then again, Swift recently told Vanity Fair that her favorite brand of underwear is Victoria's Secret, so perhaps she doesn't know from reason.

(Images via Getty, h/t: ONTD)