The best replacement for web service is wcf.

The best alternatives to web service are rated as following:
★★★★★  wcf
★★★★  web application
★★★★  windows service
★★★★  api
★★  servlet
★★  wcf service
★  rest
★  ejb
★  jms
★  remoting
★  dll
★  rest api
★  web site
★  web server
★  soa
★  direct database access
★  rpc
★  web method
  web service
  stored procedure
  ftp
  http request
  rmi
  .net remoting
  http post
  message queue
  http
  odbc
  mq

Your alternative for web service is not listed? Suggest!
Speaking about web service, one probably shouldn't forget about asmx.

Other search terms related to web service and their ratings are:
★★★★★ asmx
You have in mind a companion for web service and it is not yet here? Propose!



Google Trends

Scale is based on the average worldwide traffic of web service in all years. Click on graph for more.
web service
wcf
web application