1. Ubuntu 11.04
1.1. Pros:
1.1.1. 1
1.1.1.1. You can buy applications (or sell) from the Ubuntu Software Center.
1.1.2. 2
1.1.2.1. All of the system settings are gathered in one window makes the administration of the OS much easier
1.2. Cons:
1.2.1. 1
1.2.1.1. there is no way to customize the docks. Users can not change the location of the dock or change its size.
1.2.2. 2
1.2.2.1. The system settings now is under Power Button
1.3. http://bit.ly/flNMKJ
2. Windows 7
2.1. Pros:
2.1.1. 1
2.1.2. 2
2.2. Cons:
2.2.1. 1
2.2.2. 2
3. Mac OS X
3.1. Pros:
3.1.1. 1
3.1.1.1. Continues to support PowerPC applications via the "Rosetta" framework.
3.1.2. 2
3.1.2.1. Improved VoiceOver for the visually impaired.
3.2. Cons:
3.2.1. 1
3.2.1.1. the higher incidence of software-hardware conflicts that will automatically ruin the user experience that made OS X famous in the first place.
3.2.2. 2
3.2.2.1. taking into consideration the fact that a bigger user base translates into a higher variety of software running on the OS, the number of security holes will also increase, a fact that can only mean a poorer experience for the OS users.