How about you actually TRY the app? If it's good, go ahead an give it a favorable review, but include full disclosure that you're an employee. That way there is no question of whether you're astroturfing or not.
I've tried A LOT of PVR software over the years, and MythTV (via Mythbuntu) is what I'm currently using. That said, if you're looking for a Windows solution to run under XP, I found GB-PVR to be about an excellent choice. There are a ton of plugins available as well, so I'd say it is at least as full-featured as MythTV. If you insist on running Windows on your PVR, you could do much worse.
*disclaimer* I've not tried Media Center under Windows 7. I did try it under Vista and found it somewhat lacking.