A while ago I started a poll where I asked developers whether they develop or use existing web services in the context of their software projects. I tried to cover some of the most important options and the poll results were, frankly saying, surprising to me. I received a total of 133 votes, a good amount to track the usage I was looking for.
First of all, I found out that most of the people who voted in this poll developed (or are currently developing) Java web services (54 votes). You might say that there aren't that many Java-powered web services in public access today, and here I would have to agree. However, Java is actively used in enterprise environments (J2EE comes to mind) and that's where Java web services shine. I am not saying that Java is somewhat of a superior platform for enterprise development, but it certainly has its well-established niche there. Chances are that people who voted for this option work in large development environments.
Second place is taken by "50% development / 50% consumption" (24 votes). I've intentionally left this as a platform-independent option because when the usage and development is split, chances are that developers don't really care about the platform in which the consumed services are developed unless specific strict dependencies are present. An important thing to mention here is that consumption here does not include the consumption of own services - only those provided by someone else, usually a public service via a web API. A good example could be Twitter or Flickr. Or web services used internally. Speaking about myself, this is the category where I think I could include my own development process - I do develop my own WCF services, but a lot of my time is also spent developng abstraction layers on top of existing web services where I have little or no information on what platform was used to develop those.
.NET developers go next with 16 votes, a number much lower than I expected. In this category I included both developers who work on old-style XML services and WCF services. The number is constantly rising and there is a multitude of .NET-based web services used both in public and internally. There are still lots of old-style ASMX services used (also known as XML web service), but those are slowly replaced by WCF due to architecture and interoperability improvements.
13 developers who voted in this poll mentioned that they consume existing web services. This category includes people who work on different service clients based on existing REST APIs and/or other types. These people might also develop services, but the key word for this option was "mainly" - this means that the majority of those who voted for this option spend most of their development time (when it comes to web services) building applications on top of existing service layers rather than working on their own services.
There are 9 developers who selected PHP as their web service development platform. Compared to other platforms, PHP might lack some development tools when it comes to heavy web service building and customization so maybe that is one of the reasons for such a low number of PHP service developers, but PHP itself supports OAuth, SOAP, XML-RPC and SCA so it is in no way a platform that can't be used to build large service layers.
It was not really surprising for me to see 6 developers who voted that they do not plan on developing and consuming web services. There are lots of system developers out there who work on a lower level than web services (e.g. C/C++ for system components, Assembler for hardware interop) therefore in the near future they don't see a need in using any web services mainly because of their development area.
The rest of the indicators are really low. 5 developers worked on web services using a platform that was not listed as an option in my poll. 4 developers plan to consume web services but they have not done this before. Only 2 developers mentioned that they plan on starting web service development.
The poll generated some interesting results that were a bit different from what I expected - I didn't think of such a major drop in numbers between platforms used for web service development, but generally it showed that web services are actively used and developed in various domains.