If a device can inspect a single application, then you could call it an appication firewall. Problem is there are tens of thousands of applications, so no single vendor can encompass them all. Obviously, some are more important than others, such as HTTP. Certainly, companies like Palo Alto seem to be comfortably ahead of Cisco, and cheaper, offering things like fully embedded IPS and ability to proxy HTTPS so that it can be inspected.
If Microsoft applications are very important, then their TMG firewall has an obvious advantage too, because no one will better understand how their own applications should function. I think it can publish applications such as Sharepoint, so it can better secure connectivity.
Cisco does have the CX module, but it's quite expensive and, at least for the time being, only available on their top of range 5585-X series appliance. I could be wrong, but don't think the CX will proxy HTTPS connections.
If I've misunderstood and you're actually thinking more along the lines of outbound web filtering, then the Cisco IronPort Web Security Appliance (WSA) is very good.
