Something's wrong, then, as I don't have those issues with Mountain Lion, and didn't have them with Lion, either.
One sentence in your post confuses me.....you say that your computer tells you that the device has not been ejected properly even after nothing has been attached or removed? In other words, if you reboot your Mac, it's going to tell you this even though you didn't put a memory card in or plug your iPhone in?
Once the computer comes out of sleep mode in the morning is when I get the message that you have not properly ejected. No phone, memory card or any other device was removed. I find with the new update that you have to eject everything in itunes for iphone, ipads etc, and eject cards from iphoto or on the desk top. The keybord eject doesn't work. In the last version you didn't have to do this step.
Since upgrading to OS X lion I have had nothing but problems, When iphone 4S is attaches, or camera memory card in inserted, it does not open iphoto to import images.
See Mac section of the article, Importing personal photos and videos from iOS devices to your computer and follow the link to "enable the behavior."
Forgot to write in my previous response is that perhaps something happened to your iPhoto preferences during the upgrade to Lion. So, in iPhoto > Preferences > General tab, check the setting for "Connecting camera opens." If it shows No application, click on that and choose iPhoto from the drop down menu of options.