> regsvr32.exe "C:\Users\jshaughnessy\AppData\Roaming\Google\Google Web Toolkit\Developer Plugin\IE\Win32\oophm.dll"
To run in dev-mode (aka "hosted mode") you'll need to download and install a gwt dev plugin to the browser in question. This is typically painless as the browser will typically prompt you and run through the install. A couple of notes:
You may need to explicity allow the plugin to get installed. Watch for browser messages indicating that it may be blocked or need permission to be installed.
On IE you may need to actually register the plugin. If you install the plugin but it does not seem to get recognized (IE keeps prompting you to install it again) then you may need to actually tell IE it's there by executing the following command (substitute with the valid path for your env) :
> regsvr32.exe "C:\Users\jshaughnessy\AppData\Roaming\Google\Google Web Toolkit\Developer Plugin\IE\Win32\oophm.dll"