Sandboxing is mandatory beginning in about two weeks for App Store applications. Get ready for loss of useful features. Is is worth it? Perhaps as a preventive measure for the future.
The Apple hammer falls on all nails that need pounding down. Meaning that useful features for some apps, e.g. productivity features used by advanced users just won’t be allowed if a developer wants to sell at the App Store.
The developer of SourceTree discusses the implications for their application.
Complying with the sandboxing rules would force us to change SourceTree in ways that would remove features, damage the usability of the app, and hurt our users; therefore, we will no longer submit SourceTree updates to the Mac App Store after March 1st, 2012.
Whether this is a trend is unclear— some categories of apps are definitely imparied by the new sandboxing rules, and for these apps, the App Store requirements are a nightmare. Other apps are on the fence, and those developers might just weight sales against features— users will lose features, and gain... nothing at present. Sandboxing is a good idea, but at present it is a solution in search of a problem (on the Mac).