I've been wanting to write this for a while.
When I read you need ruby to generate themes, I nearly dropped ExtJS and Sencha Touch on the spot. It was that big of a shock. It isn't what you promised, in the spirit of where this community has come from, and it doesn't serve the majority of the community, rather some internal development niche. Seems like your 'community' doesn't matter as much as your consulting arm. Should we just start using jQuery instead?
I'm not installing that ruby rubbish on my computer, ever. To think that a client-side framework would tie themselves to a generator that is so niche is a seriously limiting business decision and a community killer.
I get asked all the time in other forums how to use LESS with Sencha Touch and ExtJS. People are really surprised there isn't released LESS templates. I'm seriously worried that the internal politics (and egos) that led to this decision will mean that Sencha's frameworks will become purely ruby front-ends, with three community members.
I've heard the excuses, but people want to use what they know. Politics aside, this solution also WORKS, so put your pointy hats away and LISTEN.
Can you please release LESS versions of your templates AS WELL in the next release.