A form isn't tabular data.
It's so easy to lay out form elements with CSS, I don't see any value worth obfuscating the markup with tables.  Personally, I find that laying out forms with CSS is easier than using tables at this point.  For example:
HTML:
<fieldset>
  <label for="FirstName">First Name</label>
  <input type="text" id="FirstName" />
  <label for="LastName">Last Name</label>
  <input type="text" id="LastName" />
  <label for="Age">Age:</label>
  <select id="Age">
    <option>18-24</option>
    <option>25-50</option>
    <option>51-old</option>
  </select>
</fieldset>
CSS:
fieldset {
  overflow: hidden;
  width: 400px;
}
label {
  clear: both;
  float: right;
  padding-right: 10px;
  width: 100px;
}
input, select {
  float: left;
}
Using simple variations on that theme, you can make great-looking, accessible forms that are actually easier to work with than tables anyway.  I've used that basic approach and ramped it up to some fairly complex, multi-column data entry forms too, no sweat.