Webservice can be accessed over HTTP protocol . Remoting can be accessed over any protocol (including TCP, HTTP, SMTP etc)
2) Interoperability :
Webservices support interoperability across platforms, and are ideal for heterogeneous environments. Remoting requires the client be built using .NET, enforcing homogenous environment.
3) Ease of programming :
Webservice is easy to create and deploy . Remoting is complex to create
4) State Management :
Webservices are stateless . Remoting support for both stateful and stateless environments through Singleton and SingleCall objects