I found that Lions does not like the Sleep Function of Mac OS X. When I wake the iMac, some of my periferals like EyeTV netstream and Drobo (connected via FW) often loose connection with my iMac, i.e. they are not recognized by the system anymore. This malfunction crashed my whole iTunes Library located on the Drobo so iTunes does not recognize the iTunes Libs on the Drobo at all - neither the actual nor those located in the "Previous..." folder. In addition often enough after a restart of Lion the network connection over WIFI takes long time to establish, sometimes doesnt at all and gives the dialog box - No Internet Connection. Seems there are a good deal of bugs at hand.
iMac 27 i7, iPad 2 WIFI, iPhone 4, Mac OS X (10.7)