Deployed on production already (http://cdn.mybucket.co/static/js/jquery-1.5b1.mini.js). I minify it using Crockford's jsmin script.
We happened to use http://www.infinite-scroll.com, which also bind to window scroll event as well. Let's see how it goes.
Thank you so much for all the hard work that goes into jQuery.
It would really help us out if people could slip our pre-release versions into their test environments. There's a 1.5 beta available now (http://blog.jquery.com/2011/01/14/jquery-1-5-beta-1-released...). Don't wait several months to try it the way Twitter waited on 1.4.4, or we may ship 1.5 with some bug that impacts your site.