I agree that Reggie is an intelligent and capable businessman, marketer and COO. The launch lineup is certainly a very solid one, and although it's really NCL's decision, I'm sure he'll do a great job selling games like NSMBU and Nintendoland and soforth, as he's shown himself capable of before. The problem is when it comes to targeting "core" gamers. Although he's got games like Assassin's Creed, Call of Duty, Madden, etc., coming out, anyone with access to NPD data could have immediately identified these franchises as ones to secure. Just having these on the roster isn't enough to win over that new audience, though, you have to convince them to switch from their current platform, or to choose Wii U over the alternatives.
To really set the Wii U up as a serious contender for "core" gamers, it'll need a number of big-budget exclusive franchises targeting them early in the system's life. We haven't been given any indication that there are any (and even though one's probably coming from Retro, we don't even know that for sure). This doesn't just impact on gamers, it impacts on developers too. If they see Nintendo unveil their new console without any significant push to "core" gamers, there's a good chance they're going to drop any "core" projects they had planned for the console on the assumption that the audience just won't be there. I wrote a long-winded post a while back about the importance of Nintendo shifting into an equilibrium where the console is taken seriously as a platform for "core" games, but I haven't gotten any indication that they're actually making that shift, and at the moment I don't see what's going to draw "core" gamers or developers to the system.
There's also the matter of actually marketing these games, and marketing the system to the people who play these games. I hope I'm wrong, but I don't have enormous faith in Reggie's ability to do either.