Mira, esta es la estructura de Youtube...solo deje un ítem pues con el XML que estoy trabajando es muy largo, mientras haré unas pruebas con o que sugeriste.
Código HTML:
<?xml version='1.0' encoding='UTF-8'?>
<rss xmlns:atom='http://www.w3.org/2005/Atom' xmlns:media='http://search.yahoo.com/mrss/' xmlns:openSearch='http://a9.com/-/spec/opensearch/1.1/' xmlns:gd='http://schemas.google.com/g/2005' xmlns:yt='http://gdata.youtube.com/schemas/2007' version='2.0'>
<channel>
<description></description>
<atom:id>tag:youtube.com,2008:user:ConcienciaCivicaJal:uploads</atom:id>
<lastBuildDate>Thu, 04 Feb 2010 00:06:03 +0000</lastBuildDate>
<category domain='http://schemas.google.com/g/2005#kind'>http://gdata.youtube.com/schemas/2007#video</category>
<title>Uploads by ConcienciaCivicaJal</title><image><url>http://www.youtube.com/img/pic_youtubelogo_123x63.gif</url>
<title>Uploads by ConcienciaCivicaJal</title><link>http://www.youtube.com/profile_videos?user=ConcienciaCivicaJal</link></image>
<link>http://www.youtube.com/profile_videos?user=ConcienciaCivicaJal</link>
<managingEditor>ConcienciaCivicaJal</managingEditor>
<generator>YouTube data API</generator>
<openSearch:totalResults>54</openSearch:totalResults>
<openSearch:startIndex>1</openSearch:startIndex>
<openSearch:itemsPerPage>25</openSearch:itemsPerPage>
<item>
<guid isPermaLink='false'>tag:youtube.com,2008:video:w14gfgb-ax4</guid>
<pubDate>Mon, 01 Feb 2010 01:56:05 +0000</pubDate>
<atom:updated>2010-02-02T16:42:23.000Z</atom:updated>
<category domain='http://schemas.google.com/g/2005#kind'>http://gdata.youtube.com/schemas/2007#video</category>
<category domain='http://gdata.youtube.com/schemas/2007/categories.cat'>News</category>
<category domain='http://gdata.youtube.com/schemas/2007/keywords.cat'>Conciencia Civica</category>
<category domain='http://gdata.youtube.com/schemas/2007/keywords.cat'>Prensa</category>
<category domain='http://gdata.youtube.com/schemas/2007/keywords.cat'>Jalisco</category>
<category domain='http://gdata.youtube.com/schemas/2007/keywords.cat'>Salvador Cosío</category>
<category domain='http://gdata.youtube.com/schemas/2007/keywords.cat'>Gaona</category>
<category domain='http://gdata.youtube.com/schemas/2007/keywords.cat'>Politica</category>
<category domain='http://gdata.youtube.com/schemas/2007/keywords.cat'>Conciencia</category>
<category domain='http://gdata.youtube.com/schemas/2007/keywords.cat'>Civica</category>
<category domain='http://gdata.youtube.com/schemas/2007/keywords.cat'>Manuel Castelazo</category>
<category domain='http://gdata.youtube.com/schemas/2007/keywords.cat'>Manuel Estrada</category>
<category domain='http://gdata.youtube.com/schemas/2007/keywords.cat'>Parlamento de Colonias</category>
<category domain='http://gdata.youtube.com/schemas/2007/keywords.cat'>Salvador Caro</category>
<category domain='http://gdata.youtube.com/schemas/2007/keywords.cat'>Villas panamericanas</category>
<category domain='http://gdata.youtube.com/schemas/2007/keywords.cat'>El Bajio del Arenal</category>
<title>Salvador Caro se compromete a ayudar</title>
<link>http://www.youtube.com/watch?v=w14gfgb-ax4&feature=youtube_gdata</link>
<author>ConcienciaCivicaJal</author>
<gd:comments><gd:feedLink href='http://gdata.youtube.com/feeds/api/videos/w14gfgb-ax4/comments?v=2' countHint='0'/></gd:comments>
<media:group>
<media:category label='Noticias y política' scheme='http://gdata.youtube.com/schemas/2007/categories.cat'>News</media:category>
<media:content url='http://www.youtube.com/v/w14gfgb-ax4?f=user_uploads&app=youtube_gdata' type='application/x-shockwave-flash' medium='video' isDefault='true' expression='full' duration='318' yt:format='5'/>
<media:content url='rtsp://v1.cache7.c.youtube.com/CigLENy73wIaHwkea_4GfiBewxMYDSANFEgGUgx1c2VyX3VwbG9hZHMM/0/0/0/video.3gp' type='video/3gpp' medium='video' expression='full' duration='318' yt:format='1'/>
<media:content url='rtsp://v4.cache7.c.youtube.com/CigLENy73wIaHwkea_4GfiBewxMYESARFEgGUgx1c2VyX3VwbG9hZHMM/0/0/0/video.3gp' type='video/3gpp' medium='video' expression='full' duration='318' yt:format='6'/>
<media:credit role='uploader' scheme='urn:youtube'>ConcienciaCivicaJal</media:credit>
<media:description type='plain'>Salvador Caro se compromete a ayudar y llevar el asunto al congreso para analizarlo mas a fondo.</media:description>
<media:keywords>Conciencia Civica, Prensa, Jalisco, Salvador Cosío, Gaona, Politica, Conciencia, Civica, Manuel Castelazo, Manuel Estrada, Parlamento de Colonias, Salvador Caro, Villas panamericanas, El Bajio del Arenal</media:keywords>
<media:player url='http://www.youtube.com/watch?v=w14gfgb-ax4&feature=youtube_gdata'/>
<media:thumbnail url='http://i.ytimg.com/vi/w14gfgb-ax4/default.jpg' height='90' width='120' time='00:02:39'/>
<media:thumbnail url='http://i.ytimg.com/vi/w14gfgb-ax4/2.jpg' height='90' width='120' time='00:02:39'/>
<media:thumbnail url='http://i.ytimg.com/vi/w14gfgb-ax4/1.jpg' height='90' width='120' time='00:01:19.500'/>
<media:thumbnail url='http://i.ytimg.com/vi/w14gfgb-ax4/3.jpg' height='90' width='120' time='00:03:58.500'/>
<media:thumbnail url='http://i.ytimg.com/vi/w14gfgb-ax4/hqdefault.jpg' height='360' width='480'/>
<media:title type='plain'>Salvador Caro se compromete a ayudar</media:title>
<yt:duration seconds='318'/>
<yt:uploaded>2010-02-01T01:56:05.000Z</yt:uploaded>
<yt:videoid>w14gfgb-ax4</yt:videoid>
</media:group>
<yt:statistics favoriteCount='0' viewCount='7'/>
</item>
</channel>
</rss>