Eclipse started as a tool in the deepest reaches of IBM's research labs. It became the powerhouse it is today under the auspices of the Eclipse Foundation. Now this open-source marvel rivals Linux and the Apache Web server in terms of popularity and use.
Choosing Java as the Eclipse implementation greatly simplifies support on a wide range of host platforms. Many IDEs only run on Windows. Some add Linux to the mix.
Several factors push Eclipse ahead of most other IDE alternatives. Its open-source support, plug-in architecture, and multiplatform support are key. But often, third-party support is the real hook. Third-party vendors know how time-consuming it can be to integrate with an IDE and how important it is to make that integration as simple and as seamless as possible.
Eclipse shines as applications require support for a range of languages, environments, and tools. Blending XML, Java, C/C++, and the latest technology (such as AJAX on a multicore, multiplatform target system) is possible with the right mix of plug-ins. At this point, the trick is finding the right choice among the variety.
Eclipse's ability to be an application target platform shouldn't be overlooked. It permits integration of the development environment and the application, even if the final delivery won't include the development tools.
So will Eclipse obviate the need for any other IDE? Unlikely. Too many other factors are in play. Microsoft's Visual Studio, for one, will likely remain on Windows platforms, due to its large and loyal following.
The other factor holding back other large IDE vendors is the size of their current audience and the investment in their current platform. Making an Eclipse plug-in isn't difficult. But creating an integrated suite of plug-ins to match the functionality found on other IDEs is no small task either. In most cases, the decision isn't whether to switch, but when.