First off, why not just put these two in CSS as a "start point"?
$('div[id*="panel"]').hide();
// make the panels absolute positioned
$('div[id*="panel"]').css('position', 'absolute');
Second, if you just move your mouse over stuff repeatedly, you get a:
Stack overflow at line 25
Webpage error details
User Agent: Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1; Trident/4.0; .NET CLR 1.1.4322; .NET CLR 2.0.50727; .NET CLR 3.0.04506.30; MDDR; .NET CLR 3.0.4506.2152; .NET CLR 3.5.30729; InfoPath.2; OfficeLiveConnector.1.3; OfficeLivePatch.0.0)
Timestamp: Fri, 5 Mar 2010 14:21:26 UTC
Message: 'guid' is null or not an object
Line: 25
Char: 10976
Code: 0
URI: http://ajax.googleapis.com/ajax/libs/jquery/1.2.6/jquery.min.js
Message: 'undefined' is null or not an object
Line: 21
Char: 560
Code: 0
URI: http://jsbin.com/js/render/edit.js
Message: 'undefined' is null or not an object
Line: 21
Char: 560
Code: 0
URI: http://jsbin.com/js/render/edit.js
Message: 'undefined' is null or not an object
Line: 21
Char: 560
Code: 0
URI: http://jsbin.com/js/render/edit.js
Thirdly, you have
var link_rel = null;
then later in the code allocate a NEW variable of the same name:
var link_rel = $(this).attr('rel');
see also
var pos = $(this).offset();
which gets reallocated each time a hover occurs.
This, along with the nesting of the elements (and position of the panel over the link) seem to lead to issues with the .hover event management.