I've got one hotmail, one live, one Yahoo and at least 5 gmail.
Heh. Me too.
Biggest advantages of Gmail over hotmail:
-Search engine is 100x better.
-Spam filter is better
-GChat
-Faster sending and receiving of emails.
-Better Android push/pull integration
-Google Now integration pulling flight status, tracking numbers, etc.
Hotmail though is much improved from the old days to the point that the format itself is now better than Gmail. The search engine though is just pathetic.