The term Douche has been used for years. It's an extremely common insult in north america but used to be reserved for guys wearing polo shirts with their collar up and perfectly gelled hair like this guy.
From the urban dictionary:
1) An individual who has an over-inflated sense of self worth, compounded by a low level of intellegence, behaving ridiculously in front of colleagues with no sense of how moronic he appears.
2) Someone who has surpassed the levels of jerk and a_sshole, however not yet reached f_ucker or m_otherf_u_cker. Not to be confuzed with douche.
I guess the term has just made it across the pond. As to it being more or less offensive, i guess it relates more to the meaning given to it. I personally think it's hilarious and use the term on a regular basis.