Here is a bookmarklet that I wrote to overcome this problem. 
To use it just save it as a regular bookmark, then when you are on the reviews page in app hub, looking at reviews in any locale, click this bookmark.

javascript:(function(){var a="https://windowsphone.create.msdn.com/ApplicationDetails/ReviewsForMarket?";var b=$("#reviewsmarketchooserdropdown option");var c=$("#ApplicationReviewsContentId");var d=0;c.html("");c.append("<div>loading <span id='countryProgress'></span>/"+b.length+"</div>");b.each(function(b,e){e=$(e);fetchUrl=a+e.val();$.ajax({url:fetchUrl,success:function(a){$("#countryProgress").html(++d);if($(a).find(".styleT").length){c.append($("<div />").addClass("styleU").append(e.text())).append(a)}}})})})()