I personally like the idea. The forum has seen a fair amount of people voice their opinion about TNA carrying a roster that is too big for them to get everyone TV time, and let's be honest, WWE gets 6 hours a week TV time, (Raw, SD, ECW, Superstars), if you're TNA, take the extra hour. I think it would help fit more on the show, and it would give them I feel one advantage.
WWE has their fans, TNA has their fans, but there's a good amount of people out there that are just wrestling fans in general. If TNA goes 3 hours (and moves to Monday Nights as is being rumored), they will border RAW, and have a full hour every Monday to gain viewers that just want to watch wrestling. Provided they can put enough on in the first hour, people will be hooked, and may not flip the channel at 9:00.
Again, they have a bigger roster, and only 2 hours a week to use it, I think the move to 3 hours can only help the company.