Should you stick to what you are starting to know?

Something that has been on my mind lately is whether it is possible to successfully write in many genres and write in them well. I have written (and not yet edited) two children's books aimed at 3 to 5 year olds. I am currently writing something that best fits into the category of 'chick-lit'. The more I get into this writing game and the more blogs I read, the more different types of book I want to write. When ever I read something by Jamila about her historical research (http://jamilajamison.wordpress.com/) it makes me excited about writing something historical and whenever I read a murder mystery novel I start to daydream about writing a thrilling masterpiece of my own.

But I have been having passing thoughts about whether it is simply better to stick to one thing.

I am on a huge learning curve at the moment. I am learning about every stage of the writing process, reading up on plotting, characters etc. I am starting to write. I haven't given much of a thought to editing and don't even mention agents or the querying process. Shudder. I had to google what a beta-reader was yesterday as I keep seeing them mentioned but had no clue what they were!

People talk of the 'conventions' of certain genres, what people expect from them. I know rules are often made to be broken but is tackling different genres with different conventions wise? Is it better to learn how to write one genre really well and put effort into that? I have also seen blog posts and articles about how hard it is for writers to be published in different genres. Now I know this is thinking way a head into the future but should I be thinking about the future? About my 'platform' as a writer? I have not completed anything but is it better I think about the future now or go with the flow? Finish my chick-lit novel (makes it sound like an easy thing to do!) and then if the next story that excites me is a mystery, write a mystery. Am I just getting over-excited by the great ideas I see and in a way being a bit greedy that I think I can conquer all these genres?

But part of me doesn't want to box myself in. Why pigeon hole myself this early? If I do get something published which seems surreal to even type, then if I write a murder mystery just for the fun of it but it never comes to anything, then I will still have had the experience. I can still say I did it.

What do you think? Do you write mainly in one genre or do you write/plan to write across several? An enquiring mind wants to know!