Both hired mercenaries/snipers to disperse demonstration, both ordered the police to kill protesters and both are corrupt dictators. Both believe that the presidency should be inherited.
Mubarak lasted 3 weeks, Assad for 2 years. The main difference being Assad has the military on his side, Mubarak didn't. Assad is a from the minority awalwite sect and so is his military which is why they're fighting the mostly Sunni rebels.
If Mubarak had full control over the military he'd be giving Bashar a good run for his money.