I have found that, with proper width in the back and proper pitch adjustment of the saddle, I do not need the cut-out. Just a channel will do. That width thing is so key for so many women!
That said, my new favorite is the Selle San Marco Glamour Aspide. I just bought it last week and did my first long ride (37 miles) with it yesterday. I loved it- kept forgetting that it was there, in fact! I was a little nervous about making such a big change before a long ride, but it paid off. It's the perfect width for me at 155mm (~6.1 inches), has a very abrupt transition from nose to tail (T-shaped), and is quite firm. The firmness really matters for me- otherwise, my "parts" get squished amongst the padding. It does not have a cut-out, just a little groove thing down the center.
http://www.performancebike.com/shop/...slisearch=true
Good luck on your saddle hunt!