It's interesting to see a comparison of apples to oranges (IDE to text editor) when you can very easily compare apples to apples - E text editor very closely resembles TextMate, works on Windows, and supports all (or almost all) of the bundles available for TextMate. It's even cheaper than TextMate.
But did you want him to compare E with Textmate? His point was that he switched to a Mac and wanted to compare what's out there for RoR on Mac: in his case, Aptana, which he was already using on Windows, and Textmate.
Two different things, true, but the former is what he was used to on Windows, and the latter a very common tool for RoR dev on Mac.
As he says in the post, that kind of decision ends up being very personal anyway. I settled on Textmate recently but I'm not sure that will be the case forever. (personally, I'd go for something in between: the speed and simplicity of Textmate with functions like the navigation between classes, auto-completion but without the slowness shown by Eclipse et al)
E is compatible with Textmate bundles, but it is not the same editor. For one thing, it's got serious stability problems. TextMate doesn't handle big files well, but it very rarely crashes.
