Hands down, the most significant mountain in chinese history, although Huangshan is reported to be the most beautiful one. But nevertheless, wheather you are seeking for stunning views or want to touch upon the ancient chinese history and culture, Mount Taishan will be a perfect choice for both options.
I climbed Taishan at the beginning of the fall on the day The Annual Taishan Climbing Contest was held. I actually took part in it and ran the half way to the top, from the center of Tai'an city to the Mid Heaven Gate. That's where you can take a cable car to the top, which I didn't. If you choose to climb on all the way up, then prepare yourself for a tough ascending. Although the main sites to see are all on the top, but the route might be rewarding as well. There are waterfals, rock calligraphy, temples etc along the way.
When you get to the top, don't forget to take a picture or two with the famous rock of Taishan. I'm not sure if it has a specific name, but four characters carved on it say: "The Most Gorgeous of Five Mounts". This is, without making things up, probably the most beautiful piece of calligraphy ever carved in rock, and it's on the 5 yuan bill for that :)
You find the rock somewhere beneath The Jade Emperor Peak.
The cable car alert above totally apply to me. I didn't know there was another cable car before (now I know there's three), so I took it when it was time to go back. Well... I took the wrong one. After 20 or so minutes ride I found myself in a quiet place, with no crowd and no people at all, which was rather pleasant until, after 2 hours walk, I realized I was on another slope of the Mount and the walk to the city itself might take another 2 or 3 hours.
Now I think it was fun, but don't try to repeat it. Keep the cable alert in mind if you decided to visit this truly gorgeous Mount.