I use this as a general rule:
$('a').live('tap',function(e){
// if external link then open a browser
if(String($(this).attr('href')).substring(0,4)=='http' || String($(this).attr('href')).substring(0,5)=='https'){
navigator.app.loadUrl($(this).attr('href'), { openExternal:true });
e.stopPropagation();
return false;
}
});