the notification area in the bottom of screen is annoying, can i change the place and look of it to be as in unity? "at the right top and disappears when hover over it"? and also is there an extension to change the icons of some programs from system tray to the upper panel?
The extension in 'Shell OSD' is outdated, and does not seem to work with 3.6+. A alternative extension that can be used is 'Panel OSD', which is more up-to-date, and should work with Gnome Shell 3.10+.
By default it shows the notifications on the top of the screen in the middle - using the settings (these can be opened from the extension's webpage or Gnome Tweak Tool) this can be changed to be on the top right:
The version for 3.10+ can be downloaded and installed from here
The 3.16 update removed compatibility with versions older than 3.10 - if you have a older version, you might be able to install it with:
I haven't tested this, but basically all you should need to do is get a version before this commit which removed the compatibility. Sources: extension README, http://stackoverflow.com/a/7832839/2943276