What a hot thread this is! 
There is no doubt Mao is perhaps the most important leader in modern chinese history. But one need to differentiate between the difference between important and greatness. For example, there is no doubt the current Mr Bush is an important leader in modern America history (he took american through the 9-11 conflict as well as at least 2 wars, maybe more?), but will you agree that he is a great leader to represent the American country? So all this controversy boils down to the fact that, as other had pointed out, it is a mere 30 years since Mao's dead. There ARE still lots of debate regarding his contribution to the Chinese history.
IMHO, Mao could never be in league with other great leaders like Qing Shi Huang, Han Wu Di, Tang Tai Zhong, Kublai Khan and Qian Long (the later depends on your definition for Chinese people. Officially, Chinese is composed of 5 main "tribes" of Han, Manchurian, Mongolian, Hui and Tibetan (thats why there are 5 stars in china flag) as well as other minor "tribes").
Qing Shi Huang is actually the first real Monarch (with real controlling power) in China, as well as standardising the writing of Chinese (his greatest achievement, imagine introducing a standard set of alphabet across europe), and building the great wall.
Han Wu Di defeats the northern raiders XiongNu and spread the influence of Han Dynasty to the central asia. This is the origin of silk routes. There is also unconfirmed report that some of the defeated XiongNu tribe migrated West, and perhaps becomes the precursor of Huns, which later cause havoc in Europe and downfall of the Roman Empire. Culturally, Han Wu Di established the Imperial Court system that is copied and used by ALL following dynasty until the overthrow of Manchurian in modern time.
During Tang Tai Zhong's time, he successfully wage a few important war, spreading the influence of China to neighbouring country like Korea and Japan, both culturally and spiritually (Buddhism to Japan and Confucian to Korea). There are also prolong years of prosperity under his rule, which leads to emergence of great artist and poets.
Kublai Khan, need i say more?
Under emperor Qian Long, china was the biggest and most populous country in the world, and marco polo even met the old emperor and describe his trip to china in his book that inspires the golden age of sails in the West.
So what did Mao achieve compared to above? He didnt overthrow the imperial manchurian dynasty, this is done by Dr Sun Yat-Sen. Although he is a lover of poetry and literature, his Cultural Revolution nearly destroy the identity of Chinese people. Just go to Korea and Japan, you will notice the traditional clothing, their way and philosophy of life. But goto modern china, can you still see any hints of traditional clothing? Not to mention the series of mistake he made in his reformations, causing millions of death in China. It is my personal belief that should Dr Sun Yat Sen not died of Liver Cancer at a relatively young age, Mao and his communist country will never had a chance to gain a foot hold in China and things will be very different...
Then again, thats why i like to play civilisation... ONLY... IF...

There is no doubt Mao is perhaps the most important leader in modern chinese history. But one need to differentiate between the difference between important and greatness. For example, there is no doubt the current Mr Bush is an important leader in modern America history (he took american through the 9-11 conflict as well as at least 2 wars, maybe more?), but will you agree that he is a great leader to represent the American country? So all this controversy boils down to the fact that, as other had pointed out, it is a mere 30 years since Mao's dead. There ARE still lots of debate regarding his contribution to the Chinese history.
IMHO, Mao could never be in league with other great leaders like Qing Shi Huang, Han Wu Di, Tang Tai Zhong, Kublai Khan and Qian Long (the later depends on your definition for Chinese people. Officially, Chinese is composed of 5 main "tribes" of Han, Manchurian, Mongolian, Hui and Tibetan (thats why there are 5 stars in china flag) as well as other minor "tribes").
Qing Shi Huang is actually the first real Monarch (with real controlling power) in China, as well as standardising the writing of Chinese (his greatest achievement, imagine introducing a standard set of alphabet across europe), and building the great wall.
Han Wu Di defeats the northern raiders XiongNu and spread the influence of Han Dynasty to the central asia. This is the origin of silk routes. There is also unconfirmed report that some of the defeated XiongNu tribe migrated West, and perhaps becomes the precursor of Huns, which later cause havoc in Europe and downfall of the Roman Empire. Culturally, Han Wu Di established the Imperial Court system that is copied and used by ALL following dynasty until the overthrow of Manchurian in modern time.
During Tang Tai Zhong's time, he successfully wage a few important war, spreading the influence of China to neighbouring country like Korea and Japan, both culturally and spiritually (Buddhism to Japan and Confucian to Korea). There are also prolong years of prosperity under his rule, which leads to emergence of great artist and poets.
Kublai Khan, need i say more?
Under emperor Qian Long, china was the biggest and most populous country in the world, and marco polo even met the old emperor and describe his trip to china in his book that inspires the golden age of sails in the West.
So what did Mao achieve compared to above? He didnt overthrow the imperial manchurian dynasty, this is done by Dr Sun Yat-Sen. Although he is a lover of poetry and literature, his Cultural Revolution nearly destroy the identity of Chinese people. Just go to Korea and Japan, you will notice the traditional clothing, their way and philosophy of life. But goto modern china, can you still see any hints of traditional clothing? Not to mention the series of mistake he made in his reformations, causing millions of death in China. It is my personal belief that should Dr Sun Yat Sen not died of Liver Cancer at a relatively young age, Mao and his communist country will never had a chance to gain a foot hold in China and things will be very different...
Then again, thats why i like to play civilisation... ONLY... IF...