Are you talking about the entire left panel - or the panels within the
map?
The left panel (where the directions are shown) on
maps.google.com
could be easily reproduced using CSS and JQuery.
Your page will look something like:
<body>
<div id="left-panel">Stuff you want in the panel</div>
<div id="map-canvas"></div>
</body>
Then, you will give your map-canvas and left-panel divs the CSS
stylings you need to make them look like google maps. E.g. float both
to the left, then either use fixed pixel widths or percentages for
height/width. I use a form of sliding panel and actually get the width
by checking a users screen.width(); then computing the width in pixels
from that. In JQuery there are a couple of options, you will probably
want to use .animate() to get the left/right sliding motion. If you
want to really make it look like google maps you can then add
shadowing onto the map div. Use a css3 shadow property with 'inset' to
make it an inner shadow and add that to the map-canvas css.