>>I thought RSS feed had a protocol. If it is, why is it that some feeds have a field in the XML structure named lastBuildDate for the last date of the build and others dc:date? Or, is there simply one way of detecting that as everyone is using its own structure?
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>the dc: is simply a namespace prefix and there's never any guarantee that a feed is not 'namespaced'. To reliably parse all feeds you need to make sure you check the actual RSS protocol/version used since this makes a big difference.
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>It's a nice mess as usual with XML protocols <g>... standards start out with relatively simple protocols and then someone decides they needs some esoteric extension and screw up the simple format for a nasty complex one.
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>OTOH, Atom is probably where things are headed and it's a pretty clean protocol still... Most current feeds use RSS 2.0 which is the easiest of the bunch.

Could there be possibilities that some feeds use RSS 2.0 but they don't include it in their XML?