Seeing that YQL is being promoted as a good way to do things, I was curious as to how to use YQL to fetch and merge 2 different feeds into one (sorted by pubDate).
It's pretty trivial to fetch 2 feeds but it turns out that the feeds are just concatenated together and not merged.
Here's the sample code.
select channel.title,channel.link,channel.item.title,channel.item.link
from xml where url in(
'http://code.flickr.com/blog/feed/rss/',
'http://feeds.delicious.com/v2/rss/codepo8?count=15',
'http://www.stevesouders.com/blog/feed/rss',
'http://www.yqlblog.net/blog/feed/',
'http://www.quirksmode.org/blog/index.xml'
)