I stopped using Eclipse about a year and a half ago because the performance (on a reasonably performant Mac) was just too abysmal. I then spent a month trying other IDEs (the free ones, at least - I'm cheap), and eventually settled on JDeveloper. It's not the best, but it had enough of what I needed - which is basically just Java editing and code complete. I really don't need all the crap they shove into all IDEs these days. Most importantly, it didn't take 30 seconds every time I wanted to switch edit buffers.
At that time JDeveloper was at version 10.3.something. About six or so months ago they started releasing the 11g technology previews of the IDE. I did notice a performance hit when running, as Oracle has started adding more and more features. But now (as of December), the third release of JDeveloper's tech preview was released, and I dropped my jaw when I saw the download size: nearly 700 MB. Honestly, the 10.x release was about one-fourth (maybe one-third) of that. After seeing that behemoth download, I realized my days with JDeveloper are almost over. With that much new code/bloat, there's no way it's going to be any more performant - my initial criteria. Yes, there may may be many new, nifty features - that all support Oracle's business, I understand this. And yes, it is a free IDE, so I get what I pay for. But even for hardcore Oracle users/shops, this upgrade just looks painful.
After this experience, I am considering going back to Eclipse, but there isn't any Solaris x86 build (except the 3.2 version on blastwave.org). Not that running on Solaris is a must, but it's what I've running on lately. Oh well, time to slum and try NetBeans, once again :).