iTunes is a great media application and it's sorting, archiving, and ID3 tag management features are the best I've found. Another great feature of iTunes is that you can open independent windows for individual playlists, for the iTMS, and for the new Podcast screen. See the screenshot below for an illustration.

Open the windows
It is really simple to open a new window and this will work for any item you see listed on the left menu. Simply double-click the icon and it will open in it's own streamlined window. I say streamlined because you won't see the left menu pane or, if you have the 'browse' windows at the top, you won't see those either. This is nice because it keeps these windows small, since screen real estate can become an issue for many people.

With the Mac, you can go to the 'Window' drop down menu at the top of the screen and see a listing for each window that's open. The key command Command+1 will always take you back to the main iTunes window (or open a new one if you've closed it). The Windows version of iTunes does not have this feature, instead you can see each separate iTunes window on the taskbar and you can switch to each one using the Alt+Tab key shortcut.

How I use multiple iTunes windows
I usually have three iTunes windows open at the same time: One for my main Library, one for the iTMS, and one for the currently playing playlist. I especially find it useful to have a dedicated window open for the iTunes Music Store because sometimes there is a delay when switching back and forth from my library/playlist and sometimes it'll take a while to cue a music video and if positioned correctly, you can monitor the status in the background while you obsess over your ID3 tags in your library (come on, I know I'm not the only one that does that).