as far as I can see, and I use a Chromecast, is that you can immediately get what you're looking at on your phone/tablet/PC onto your TV with a minimum of fuss. I have an HTPC connected to my living room TV and it can do much more than the Chromecast, I should hope so given its cost, but it can't compete with using a tablet to browse the content and then get it on the TV. The 12 foot interface on none of the HTPC software I use or have used can compete with the tablet interface, having said that I only use the Chromecast for casual viewing and Netflix, other stuff still goes through my HTPC. The other advantage is portability, 5 seconds to disconnect it and then another five seconds to plug it into another TV. Oh and the price is the killer advantage of course. An ideal situation would be an app that easily interfaces and controls my HTPC via my tablet, which exists for MediaPortal in aMPdroid, but also one which will feed the URL of desired content to the HTPC, which it doesn't, for now at least.