Zapier is more business-oriented, with apps like Box, Capsule CRM, Jira, and Zendesk – it ties in with services that companies use for customer communication, internal workflows, and marketing efforts.
Other than that, Zapier has a more traditional interface, where IFTTT feels more like you are playing with a toy (not to take away from it’s power; it’s merely a very creative and fun interface).
These type of services do a great job of organizing the plethora of services out there and their associated endpoints for sending or receiving data.
It makes me wonder if we are entering a new realm of staying connected on the internet, that which is not so dependent on notifications (such as email and SMS, which require a follow-up action), and instead performs the action right away without the notification part. Who would be trying to achieve “inbox zero” if we were less dependent on inboxes in the first place?