Believe it or not sharp rounded corners will slice you good. Did you mean the corner cut you? Does the look razor square in you shaver?
Hope it wasn't too bad. I've nicked my ear, so I know where you're comin' from. That is one thing I do like about the Merkur Futur - the cap covers the edges. Can't say that I know of any blades with rounded edges.
Achim shows at least one type of blade with rounded ends, but I think they're not widely available.... mostly due to their antiquity (they're from 1919) http://mr-razor.com/Rasierklingen/1919 (951) Gillette Blade.jpg edit: eek! That's a bit of a huge image! (changed to be a clickable link)
wow..cool pics!..it was bad enough last week I nik'd myself with my feather neat my mouth area due to me being overly tired then for some reason wanting to shave..oy vey!...bled then waited about 3 days to shave again!