messy - that is indeed a brilliant comment!
JLK2 - Etymologically, I doubt oil-seed rape is anything related, is it? 
As to what rape means ... yes, words do change their meaning. But this is not what's going on here. When 'rape' used to mean simply 'take by force', yes, it'd make sense to refer to the rape of a city, or to the rape of a woman. You note that in both cases, the thing taken is just that - a thing. This does say something about those societies' view of rape, and I for one am glad that it has been quite some time since we spoke Latin.
OTOH, when people say things like 'OMG, I've been fraped again', they are mostly not returning to Latinate usage. I doubt many of them are aware of it. Instead, they're using rape in a metaphorical sense to mean 'something slightly unpleasant and intrusive of my privacy'. The problem with that is that the word isn't changing its meaning - no-one has become confused by newspaper reports of a man being convincted of rape and thought 'now, was that about myspace or what? Instead, the metaphor implies there's a resemblance between raping a person and intruding on private space. And there isn't.