Hi there. Correct me if I'm wrong: PhoneGap needs you to be online, the work goes on their servers and you must download etc the apps? (even the intro video says it). I found this very boring. Researched, read and etc. Followed instructions installing the tools and only had to upload the project to the web/cloud, then it was compiled and I had to grab it. Didn't like it much specially needing to stay online. Had some troubles creating the account finding other users with the same errors, created a new one (already had an account at Adobe) and finally got it running. I remember being able of working on one project at a time needing to pay to work on more, didn't like that.
Tried Lazarus Pascal and loved it!, read a lot and you can develop for linux, windows and mac, the problems is later I found that you need to download a whole bunch of other stuff to compile and deliver to Android. I instantly remembered my attempts with Eclipse in the sense of having to download something each step of the way, but Lazarus is something I really enjoyed, will try a bit of it later for other projects.
As for Eclipse, I tried and felt dumb with it, I had to download A, B, C... and each step made me download more and more. It was too much in my opinion to end up creating apps 1-5MB. Also felt pretty dumb because I couldn't really get along with Eclipse. My experience goes on other directions and languages.
Downloaded Titanium but haven't played with it yet.
Read a lot of good promising things about RMS (Rhomobile) from Motorola, installed it (nearly 400MB) but felt ignorant again, it's too much for me. There are other tools including 2 online, one from MIT and another I can't recall it's name BUT they address Android only, not multiplatform.
So, with Mosync you don't need to download half the web, you just need Mosync APP, Java and Node JS. It's not too heavy. I also downloaded Mosync Reload but I'm fine with the basic stuff. It's free but so far I would buy it anyway.
Lua and Corona were on my list to try but Mosync suites my needs so far. I see a lot of developers doing things in C and OC but that's too far for me.