the songs really aren't that close.

they both feature cowbell prominently, sure. there is certainly a similar feel

but they're in different keys and the melodies aren't close at all to each other. the notation is very different between songs.

is blurred lines inspired by got to give it up? absolutely.

is it a rip-off of got to give it up? absolutely not.

and it's bigger than just this case.

take your man r.kelly, for instance.

if blurred lines is a case of plagiarism,

how isn't this ripping off barry white?

love is
http://www.youtube.com/watch?v=NLuxo_TioaE

isn't feeling single basically just bill withers' 'lovely day'?
http://www.youtube.com/watch?v=WmBts29yzpA

this isn't a bit too close to stevie wonder for comfort?

clipped wings
http://www.youtube.com/watch?v=u4mKebTYOtw

(i don't have to take it all the way back to 'she's got that vibe', do i? i don't have the time).

all these songs are clearly inspired by other artists' songs in exactly the same way blurred lines is inspired by got to give it up, are they not?

and there are countless other examples besides your man's. calling for monetary compensation from songs that are inspired by other songs is a very slippery slope.