part of me is with Marty on this one, too. a large part of me. and part of me also says that in this day and age, it's so ridiculously EASY to make your own custom "best of" collection that the notion of such a thing seems ridiculous...but the thing is, who's the "best of" comp for? it's not aimed at us. it's not aimed at people who likely have most everything they want that's been released previously, and/or are on their way to getting it, and/or care enough to hunt such things down. such collections are aimed at casual listeners.
hence, why the argument i made yesterday (and deleted, cos i realised i hadn't thought it through very well) doesn't work...the idea that imports are a lot easier to find these days, so if a "best of" hasn't been released in your country properly, it's not that difficult to get hold of. again, casual fans aren't going to go to that length...or want to plunk down that money. so in that sense, it does indeed make sense that someone would want to put together a domestic "best of"...perhaps for the purpose of hooking new fans in moreso than anything else...? 
i agree. for people such as ourselves, we really do just need to have Recycle already. the concept is a lovely one, especially since some things are really difficult and/or very expensive to find. plus, the portability of CDs is a lovely thing. ;)
so i'd personally take this as, what would *i* put on a CD to try and hook new fans in? what would *i* put on a CD in order to make an otherwise casual fan go "my GOD, that's the coolest thing i've ever heard! i must have more!" 
and part of me says "to hell with it, ANOTHER stupid 'best of' comp to litter the shelves...?" 
the battle rages on. 