I’m not sure i completely concur with Tim’s post on the basic difference between IDEA and Eclipse but as a huge fan of IntelliJ’s IDE I found that it did have some truth to it. Tim says:
Since Eclipse is a free, open source application/platform, the revenue model is based on providing extensions, support, and training. If it was intuitive, easy to use, easy to extend, or a complete solution, there would be no incentive for people to pay for the services that make money.
Since IntelliJ IDEA is not free or open source, the revenue model is based on sales. Sales are driven by the quality, ease of use, and completeness of the product. If it fails in these areas, it doesn’t sell.