i like the classic subway tile. you always know it will pair well with other tiles; it gives a clean look to a space, but at times it can be a little monotonous. companies know that this classic tile is what people are using so they are trying to put a little spin on it...you can find the tile smaller or larger in size, crackled, glass, metal. you can also find different takes on the pattern which i like:
you can flip it and create a bamboo pattern (done by kwid in many bathroom applications), you can line it up in rows to create a linear look, or you can find it in a basket weave kind of pattern.
whatever you do, one thing is for sure...it looks like this tile is going to be around for a while longer. and you know, that's okay with me b/c i do think it makes for a great, simple backsplash.