I think it's all about how you wear it. Certainly, it looks hideous on people who don't have style to begin with. But, if you've got personal style, you can pull off anything. Including Crocs.
Initially, I disliked Crocs--disliked with a passion. In Hawaii, the only people I saw wearing them were too-good-for-fashion hippie-types and tourists. Neither type looked good in these shoes, but neither type was stylish. My boyfriend, on the otherhand--who does have personal style and can thusly wear everything in an 'edgy' way--got these shoes a few months ago. I have been (slowly) warming up to them ever since.
So while I was in the natural foods store the other day, stocking up on groceries, I tried them on in asphalt/gunmetal grey. I was pleasantly surprised to see that they provided an interesting counterpoint to my raw denim skinny jeans and my fitted black deconstructed sleevless blouse. Hard to believe, but true. Crocs defnintely dressed my outfit down and I don't think I'd wear them regularly, but I may buy them for my casual, running around outdoors days.
Incidentally, several people on this thread have been thinking that these shoes would make for gross, sweaty feet. I thought this too , but my boyfriend said that the shoes were antibacterial. If they weren't antibacterial, he said, he would have had stinky feet on the first day he wore them. He's been wearing them for months (like I said), and no stinky feet yet!
As for the ballet flats, I think those are definitely cute. I'd like to check those out.