Now if you are uncomfortable with this, you can easily change it back to the right hand side. (Even if you arent using Lucid Lynx beta maybe you can move the buttons to the left and see how you like it! If you dont you can obviously change it back.) Here's how you do it:
1. Press Alt + F2 on you keyboard. In the window which opens up, type gconf-editor and press enter.
2. In the Configuration Editor window, go to apps>metacity>general
3. As you can see, it has a button_layout option. This is where you will do all your tweaks. To edit the button layout you will have to double click on the "maximize,minimize,close:" option.
Now before you change anything, let me just explain the basics, so that it becomes comfy to tweak with ease. Okay, so the default button layout if you are using Ubuntu 10.04 is "maximize,minimize,close:". (If you're using 9.10, the button layout will be ":maximize,minimize,close".) Now here's the thing. Maximize, Minimize and Close stand for each of the respective buttons and the ":" after that stands for the rest of the space on the title bar.
So basically, if you type ":maximize,minimize,close" the space will shift to the left and hence the buttons will be on the right.
My favorite pattern is ":minimize,maximize,close". You can now tweak it to suit your needs. As you see, it couldnt be any easier.
Now, when you are done editing, simply press enter and you can notice the changes.
