Agreed on the long wait for Invincible. (and more spoilers to follow...)
These writers seem to have it in for Tim Zahn's characters...first Leia's Noghri bodyguards, then Mara Jade, and now Pellaeon...and I'd wager either Jacen or Jaina will have to die in the end. Thankfully Tallon Karrde decided to sit this series out, or I'm sure he'd have died by now.
Aaron Allston's books were a pleasure to read thus far (I love his take on Lando, and the humor he brings to the situation...ie the Looooove Commander.) Troy Denning's entries have been a real chore, though, I absolutely couldn't take one more Alema Rar POV passage, so I'm hoping Invincible is worth it.
Karen Traviss has been the middle of the road for me. I haven't really gotten excited about all the Mando stuff, and unfortunately she got the character of Pellaeon completely wrong. I found myself really brought out of the story quite a few times with his reaction to Jacen's control of the fleet. Seeing as he was on hand for (and very outspoken against) Thrawn's use of C'Baoth's fleet coordinating skills, I found it completely unbelievable that he would be so surprised by Jacen's actions. I was hoping for at least some acknowledgement that Pellaeon was aware of the power of a Jedi gone dark, but I guess Traviss didn't read those books to know. At least know the characters you're killing off.