let's add a few FACTS that were conveniently left out, shall we? [devil advocate mode on]
-He was captured by the Thalmor and revealed sensible information pertaining the war in exchange of his life. So much for "Glory or death"
-He was responsible for the ethnic cleansing of Bretons during the Reach campaign; other atrocities were committed in Markath as well
-He refused to help the Redguards during the second great war despite their plea.
-He used a Shout for personal gain... something the greybeards (who taught him the way of the voice) forbid, so he betrayed his masters.
1: Not correct, he was tortured for the information.
2: Source? Even the Jarl of Markarth says that Ulfric was asked to retake the city and that they offered him free worship. I take the word of a living Jarl who supports the Empire over a book written by an imperial schoolar any day.
Spoiler In the Escape from Cidna Mine quest there is also prisoners who were there that says it was the Markarth government that executed the Bretons after they managed to take the city, not Ulfric.
3: I want a source on that. Also, I am not sure he was a Jarl at the time of the request either since he didn't gain that title before after the Markarth incident.
4: Yes, he betrayed the Way of the Voice. Dishonorable? Maybe, but he was never given any chance of not getting the training as far as I am aware. He was also only a boy. I would be prone to leave High Hrothgar myself. As for the personal gain: Yes he uses the training he have to further his own agenda. Like everyone else.
On another point i have seen in the thread: The Thu'um is considered to be a weapon and a tradition of the nords. I don't see how using it is dishonorable. The thing one could claim was dishonorable was to challenge a man he knew he would defeat, but Ulfric himself says the whole duel was to prove a point.
Yes, I also like to play the devils advocate

I don't thinkn Ulfric is as bad as many portray him, but he is far from a saint.