Throwing in my 10 cents on the matter.
I was going to go on a long rant here in response to your assertion that we shouldn't have a flashy interface, but I'll spare everyone and just say that I strongly disagree.
I am not opposed to having a flashy interface at all and did not assert anything like that.
However, having flashy interfaces does not automatically mean that the user experience for users with older soft / hardware has to be bad. In many cases, it is actually pretty easy from a technical perspective to provide a reasonable experience for older browsers while still having flashy things where supported.
I agree with this. And I think that gracefully degrading should be the policy wherever possible. If I want to do things on Wikipedia from Lynx [0] I should be able to do as much as Lynx supports, not less because my useragent doesn't match something that we support.
I fear that a binary browser policy would discourage people from keeping this in mind, and think that we can do better than that.
/\ This. I also agree with this 100%.
It could be fairly easily solved though by simply mentioning that the intention of the policy is not to discourage people from making gracefully degrading interfaces. That would solve the problem of people pulling out that policy and pointing to it as a reason for why their stuff doesn't at least semi-work.
On the topic of which browsers to include, I recommend against having a hard list (Firefox, Chrome, IE, etc.). I think it would be preferable to use percentages, but keep a list of what browsers meet that criteria at any given time (preferably automatically updated). I think a static list of browser, while correct and relevant now, may not be 5 years down the line. Although everyone at the WMF and who volunteers with the WMF is a lot better about updating outdated policies than almost anywhere else I have ever seen, we all know that we have our fair share of outdated policies and documentation.
Anyhow, that's where I stand at least.
Thank you, Derric Atzrott Computer Specialist Alizee Pathology