I use it only when it's clearly obvious what var is.

clear to me.

XmlNodeList itemList = rssNode.SelectNodes("item"); var rssItems = new RssItem[itemList.Count]; 

not clear to me.

var itemList = rssNode.SelectNodes("item"); var rssItems = new RssItem[itemList.Count]; 

I use it only when it's clearly obvious what var is.

clear to me:

XmlNodeList itemList = rssNode.SelectNodes("item"); var rssItems = new RssItem[itemList.Count]; 

not clear to me:

var itemList = rssNode.SelectNodes("item"); var rssItems = new RssItem[itemList.Count];