I doubt there's really a good answer to that question. Looking for a degree is probably not the worst answer, though it may not be the best either (probably better than asking them what beverage they drink, which is presumably to establish their stuffwhitepeoplelike cred).
That's a very good question. Competent people generally know if they are better or worse than one of their peers. However, if no-one in your extended social circle is better than a mis-guided power user then you'd be unlikely to get a trusted and reliable opinion on ability.
In which case, a good proxy would be a de-emphasis on whizzy pixels. Any kid can make CSS menus and non-interactive Flash. However, how many normalise a database or install a firewall?
http://www.inter-sections.net/2007/11/13/how-to-recognise-a-...
I guess you don't need a degree to do a startup, but on the other hand, if you are young and you enjoy learning, there are worse things to do than hang around on campus of a nice university? I personally missed learning when I entered the "workforce". Sure, I try the odd new thing now and then, but it is not the same as the dedicated effort I made at university.