I'm not one to follow trends, but I suppose if you were to ask what is 'in' and 'trendy' in terms of wedding cakes at the moment, a lot of cake decorators would probably say cupcakes. Now personally, I would MUCH prefer a croquembouche to cupcakes, because it seems more formal, which is my style. I agree with what the other girls have said - don't choose anything just because it's a current trend. Choose something that reflects who you and FH are, in keeping with the theme of your wedding.
For what it's worth, FH and I chose a white 3 tier mud cake with square tiers, with gold ribbon and fresh roses separating each tier. It's a big, classic-looking formal cake (about 60cm high) and that's exactly the style we are keeping with for our wedding. A lot of people said, 'why don't you go for cupcakes, or do something that is more brightly coloured, as that would be more contemporary than an old-fashioned 3 tier-style cake', but we wouldn't hear of it.