A trend that is sweeping the nail-world right now is gradients. I think a part of this style gaining popularity is through Sammy from The Nailasaurus posting her tutorial which makes creating gradients a hell of a lot easier. You can find that here. This is the technique I used to paint my nails.
The yellow is Barry M's "Lemon Ice Cream" and the blue is Max Factor's "Candy Blue".
I've still not decided whether or not this combination is something I like. The colours are very bright and "in-your-face", but at the same time there's something hypnotising and summer-y about them.