Firefox 4 is coming very soon, and it’s now time to start marking your add-ons compatible with 4.0.*. We don’t expect any further compatibility-breaking changes in Firefox 4 betas, and any that do need to land will be announced on this blog, on MDC, and via email if we can identify AMO-hosted add-ons that are affected.
We will continue to add beta versions as they are released, but most add-ons should now begin to use 4.0.* as their maxVersion.
And as a reminder, the free Firefox 4 t-shirt offer ends on January 7, so be sure to update for beta 8, beta 9pre, or 4.0.* by then!