LemonMelon
More 5G Than Man
Too slow Traviud.
I do agree that the line is hard to draw though. The purpose of EPs can vary from genre to genre - some genres definitely place more importance on EPs (and singles) than others, as the RYM charts also show, and the normal length of an EP or an album will change a lot between genres. It does, however, seem to me that EPs sometimes unfairly get maligned, especially when for some bands - usually young bands building a reputation - an EP can be a very significant artistic statement, as important as an album.
Personally, I love EPs and think they can be useful in introducing new artists (Lorde's Love Club was a big deal) or in fleshing out established albums (a lot of them fall into this category).
The Empty Estate EP was a favorite of mine because it implied a new direction without diving right in. I wouldn't call it an album because I think the band purposely wanted to tease a new sound without a great deal of commitment to it, but it certainly was an important release for the band.