The title and the description of the Wiki RSS feed should be in the preferences.

The title and the description of the RSS feed is actually in the XWiki page in charge of the creation of the RSS feed. When a user would like to change the name of the RSS feed he must edit the page : Main.BlogRss to set the title and the description :
Like this :
$response.setContentType("text/xml")
#set ($baseurl = "http://${request.serverName}")
#set($title = "My RSS Feed")
#set($description = "My RSS Feed")
#includeForm("XWiki.BlogRssCode")

This should be great if we could have some parameters in the preferences to set the title and the description of the main RSS feed.