being metrosexual does not just encompass grooming yourself or trying to look good.
a metrosexual guy is someone who is seemingly masculine yet takes great care and expense in his looks and carriage. although he is not strictly homosexual, his behaviour and his obsessiveness (might be too strong a word) with looking good may suggest the opposite. he does not have real interest in women, although he occasionally dates them to "add up". he is primarily more concerned in his appearance than really commiting himself to a relationship.
of course, i'm not metrosexual.