I think I might accidentally end up two timing

[squarehead]

This might sound a bit weird, and so far it has not yet turned into a great big problem (and hopefully it won't), but it is a potential problem that I'm hoping to get some thoughts on.
I am on an internet dating site. I'm kind of half-heartedly looking. Anyway, I recently read the profiles of two different men, and I sent a message to them both. Nothing much, just suggesting friendly conversation between us. To be honest, I was not expecting any enthusiasm (being as I told on my own profile that I have children, and to a lot of men that is a put off). However, both of them have showed an interest, and both want to see a picture of me and to chat...
So, what do I do? Is it bad dating site etiquette to get to know two men at the same time? Obviously, it is only on a friendship level anyway to begin with, but we all know that it is with a view to more happening if we end up hitting it off.
Should I just pick one, and phase out the other? Should I 'two-time them' anyway, and just hope that I don't fancy them both, and attract them both?
Should I tell them about each other?
Is it a big deal?
I know it sounds ridiculous because in all probability it will not go beyond a few e-mails in either case, but I am just dreading a situation where I get sucked into a web of deceit, and lead one of them on.
Please tell me what to do?
Anyone with experience?

Message withdrawn

Thanks for all the feedback. So, the general consensus is that it is not two-timing unless it goes further than just chatting and meeting up. Does that also apply when we are not local, so in order to meet up it would involve a longish journey.
So, should I casually drop into conversation the fact that I'm chatting to others? Or not mention it unless it comes up?
I suppose it feels a big deal because I know other people who have declined to chat to anyone else (on dating sites) because they are already getting to know someone.
I don't think it is something I would have done, but it just seems to have happened by accident (in that I messaged two not expecting them both to respond).

Hmmm, well we can tell you what we think the (unwritten, understood) rules are. But of course whenever you find yourself feeling uncomfortable with the situation, you need to change it.

I wouldn't bother mentioning that you're chatting to other people, I do think that's understood in these environments.