I was part of the first group in our guild to complete the 45-min Baron kill. I highly recommend doing this run. It can be frustrating as you learn the best tactics for it, but it is a very intense fight that keeps your adrenaline running the whole time. Here's a reprint of what I've posted in a couple places:
There isn't time to tank, we went mostly DPS and healing. Two DPS warriors, a rogue, a paladin for backup DPS or healing, and my priest. I was constantly drinking while pulls started, never really at full mana once the run started (I've got 313 Spirit, Blue Dragon card, and 35 mana/5). I burned about 40 Blessed Sunfruit Juice and 12 Major Mana potions during the run, and healed about 515,000 points of damage (without a lot of overhealing, there isn't time to waste mana and top people off).
It took us a few tries to figure out the optimal path. We eventually went spider, banshee, Maleki, taking the route that skips the rat gate. We skipped every group we could, pulling into small cleared areas and concentrating on killing humanoids over zombies because they have less armor. You can skip Magistrate Barthilas completely. You need to hit the Abominations with about 15 minutes left. We pulled Abominations close to two at a time, it seemed to work best with one at about 20% when the next one came in. I shackled them if the current target was going to live more than a few seconds. Holy Nova was decent on the oozelings, a little too much mana cost when healing the damage the Abominations do, but really destroyed the skeleton wave right after Ramstein.
There was a long pause before the skeleton guards came out, about a minute as we screamed at the door and beat on our desks in frustration. They finally came out, we smashed them and ran in to take on the Baron. We engaged him at about 42 minutes, and killed him by 44. We set up a rotation of Holy Water to deal with the skeleton spawns, and I used Holy Nova a couple times. I'm not sure if you just have to engage the Baron by 45 min, or actually kill him.
This may be a spoiler, but here's a screenshot of the end.
You can also see in that shot that we are not loaded up with uber gear. I think the only MC item in the group is my Girdle of Prophecy. A few other PvP or crafted purples (Unstoppable Force, Truefaith Vestments), but mostly blues.