I don't have a landline at all, and use Skype for all my telephone calls - to landlines and mobiles. You can't do that on msn.
It saves me at least �11 a month in telephone line rental..
I use it to instant message (like msn) with my friends.
Best of all, I have registered my mobile phone with it. I can send texts to any mobile phone for 5p and it shows as coming from my phone, not skype. So much easier to use a keyboard than the phone keypad. Texts back are received by my mobile phone.
I have a SkypeIn phone number which looks exactly like any other landline number, and people get charged usual landline rates to call me.
I have a skype phone, which is wireless - looks and behaves exactly like any other phone, but connects to the internet via my wireless router, so my pc does not have to be turned on to use Skype.
It has an answer phone, caller display and so on.