Venmo isn't money over IP - it's Paypal with a mobile/social interface. Bitcoin is money over IP because it's a protocol for transferring value between users on the internet, and it's a platform for higher-level services.

Venmo isn't a distributed protocol or platform, it's a centralized single entity that removes some of the friction in transferring USD within US borders. It's still subject to all the problems of Paypal - that of arbitrary account suspensions, seizures, and blocking of payments.

You can't use Venmo to transmit money internationally, store value without fear of seizure, hedge against inflation, purchase goods/services with relative privacy, activate an online business instantly, engage freely in voluntary transactions with anyone on the planet, accept payments without risk of chargebacks, and so on.

Bitcoin and Venmo offer different value propositions. Venmo is more of a threat to Paypal than it is to Bitcoin.