Is there any way to get the URL to open in a new browser window?

Thanks for responding.  As a workaround, I left the Map URL blank and modified the EventDetails template to build various map urls containing query string parameters.  I used the Location (city) and two custom fields (street address and zipcode) as the query string parameters, then set the target=locMap to open in a new window. (Note: in my case, all events are in Florida so I hardcoded that into the query string.)  Examples are below.

<a href="http://maps.bing.com?where1=[event:customfield1] [event:location] FL [event:customfield2]" target="locMap">Bing</a>
<a href="http://maps.google.com?q=[event:customfield1] [event:location] FL [event:customfield2]" target="locMap">Google</a>
<a href="http://maps.yahoo.com?q1=[event:customfield1] [event:location] FL [event:customfield2]" target="locMap">Yahoo</a>
<a href="http://www.mapquest.com/maps?city=[event:location]&state=FL&address=[event:customfield1]&zipcode=[event:customfield2]" target="locMap">MapQuest</a>