Dragging the Library folder to your favorites list in the Finder unhides it.
On LifeHacker today, there is a post about an Applescript that unhides the Library folder on your Mac. I haven't tried it to verify it works, but there is a faster way to make the Library folder visible.
For most Mac users, the Library folder remains out of sight, out of mind. When Apple rolled out Mac OS X Lion, it decided to hide the Library folder, which houses preferences and settings that help keep the OS and your apps running smoothly. If you are the curious or the restless type and need regular access to the hidden Library folder, here's a tip to add it to your Favorites.
To access the Library folder, open the Finder and then, while viewing the Go pull-down menu, hold down the Option key to see the Library. It shows up between the Home and Computer menu options. Open the Library folder and select the column view so that you can see the Library folder itself (and not just its contents). Simply drag the Library folder to the sidebar to add it to your favorites, where it will remain visible.
Now, I don't know if it will disappear after the next Mac OS X update, but it's not that difficult to add it to your favorites again if it fails to make the leap.