What should I know about working with FBML in Facebook?

I've been tasked to develop a fairly simple reservation console for a hotel. It features two <form>s which have corresponding tabs, the active tab applies to the default form and the inactive tab applies to the hidden form. The tabs are clickable and would enable/disable their respective forms.

So far what I am planning is having embedded style and script elements below my main HTML.

Question 1.1: For the HTML, can I just go ahead and straight up do what I want, or am I restricted? Do I have to use any facebook specific elements for plain old stuff like forms?

Here's an example of a snippet I would use:

<ul>
    <li id="tab"><a href="#blah">text</a></li>
    <li id="tab2"><a href="#blah">text</a></li>
</ul>
<form id="hidden">blah</form>
<script>
(function() {
var tab = document.getElementById('tab'),
    tab2 = document.getElementById('tab2');
    tab2.onclick = function() {
        document.getElementById('hidden').sty开发者_开发知识库le.display='';
        return false;
    }
})();
</script>
<style> #hidden { display:none; }</style>

Question 1.2: Are there pitfalls with this code? Is it bad to rely on private namespacing / anonymous functions because of the way Facebook converts the markup and js? Should I be using inline event handlers such as onclick for event based behavior because it would be easier for the Facebook "converter" to parse it and "recompile" it?

Other background info:

This widget does not have any sort of share buttons, login, pictures. It pretty much will consist of an arrival/departure textfield, dropdowns for adults/kids, and an submit button. This goes for both forms.

The main thing to know about FBML is that Facebook has deprecated FBML pages in favor of iframe pages. The good thing about using the new iframe pages is that you are pretty much able to do whatever you want on your page in terms of css, html, and javascript. There were a lot of gotchas as you were asking about with FBML but a majority of those have gone away.