[cloudsec9]

Either your business model and philosophy embraces open source, or it doesn't -- I really don't see how having things on conditions helps really. All such pledges might do is give you a bit of runway, and I'm not sure how that advances things. If you have a solid biz model, then going open source helps people who might either benefit or use your software to leverage your platform -- and that can help right away. For me, if your startup is open source, even if you go poof I can still pay someone to maintain the software, reducing my business risk. Plus, if something is broken, I can get it fixed, or if I need something I can add it and possibly contribute it back.

You don't mention the area you are targeting or your biz model, so I can't help on that side. But I wouldn't be so thrilled to contribute to something that "might be" or "will become" open source. I have seen projects that do "funded development", where features are added based on customer or $$ flows -- like "feature X will cost $2k, so 10 new customers or equivalent community contributions and we'll work on it".