I honestly don't believe the ZD50-200 ever came with a plastic tripod adapter, it's far too heavy.  I've never heard of anyone complaining about a broken plastic tripod adapter on a 50-200 and I belong to just about every Oly forum on the Internet.

The lens is a joy to use, and if you remove the tripod adapter it'll lighten it up perhaps enough for you to use handheld...with plenty of practice, that is.  You'll of course get better results with a sturdy tripod.  I've gotten great results with it on both E-1 and E-500 bodies.  It also produces fairly decent bokeh.  A big plus for the lens is that it's weatherproof; you can shoot with it in the rain all day long with no fear, and living in Oregon,  I have.  Of course, you'll have to have an E-1 body to pull that one off.

Admittedly though, I find myself using the 40-150 more.  I'm seriously thinking about selling my 50-200 and replacing it with a 7-14.  But what I'm really waiting for are the specs and reviews on the E-3.  I may hop on over to Canon if the cameras aren't seriously improved.  My hopes are high though, based on the images I've seen from the E-410.  Higher ISO perfomance has become critical for me lately, as well as increased buffer/fps.

This is not to say Oly cameras take crappy pictures.  They take outstanding pictures.  I've tried them all, and I feel the Oly E series still produces the most accurate, vibrant colors, with Fuji S3/5 following a close second.

As you probably know, the E-510 and E-3 will have IS in-body, so using your new lens at the long end will become much easier if you are overcome with upgrade-itis and choose to buy the next-gen Oly body.  There is of course a newer version of the ZD50-200 on the near horizon, with much improved focus speed, but you'll have to buy the new Oly body that supports those electronics, presumably the E-3 and/or E-510.

Be sure to update the firmware for your new lens: http://www.olympusamerica.com/e1/sup_firmwareupdates.asp but you probably already knew that.
 
Probably more info than you ever needed, but I like to read myself type - lol.

Warm Regards, and enjoy your new glass.