Here's how to do a table with rounded corners in CSS3

rounded_corners_table.sass

@import compass/reset
@import compass/css3/border-radius

table
  border: none
  border-collapse: separate
  th, td
    padding: 5px
  thead
    background-color: #f2f6fa
    th
      border: 1px solid #ccc
      border-left: none
      &:first-child
        border-left: 1px solid #ccc
        +border-radius(5px 0px 0px 0px)
      &:last-child
        border-right: 1px solid #ccc
        +border-radius(0 5px 0px 0px)
  tbody
    tr
      td
        border-right: 1px solid #ccc
        border-bottom: 1px solid #ccc
        &:first-child
          border-left: 1px solid #ccc
      &:last-child
        td
          &:first-child
            +border-radius(0px 0px 0px 5px)
          &:last-child
            +border-radius(0px 0px 5px 0px)

sample_table.html

<table>
  <thead>
    <tr>
      <th>name</th>
      <th>email</th>
    </tr>    
  </thead>
  <tbody>
    <tr>
      <td>john</td>
      <td>john@domain.com</td>
    </tr>
    <tr>
      <td>jane</td>
      <td>jane@domain.com</td>
    </tr>
  </tbody>
</table>