You've probably heard this a million times already, but I must add fuel to the fire.
I just left a 4 month contracting gig at Pivotal Labs. I learned to use IDEA there and then switched to RubyMine. They are a huge customer and avid fans of the tool. But developers are starting to become fed up with the laggy performance of the tool. There's active movement among many developers to seek out new options, including going to Vim.
You should stop adding features until you can make what you have lightning fast. Your going to lose a lot of users if you don't improve the performance of the tool. I love it. I want to use it. But I really need it to be more responsive.