The current public beta patch policy allows for players who choose to use them to get muuuch faster updates from the developers and provide critical feedback during the patch development process. This feedback has been shown to have borne fruit already in the 1.03 beta patches - for instance, the mouse smoothing tweaks were adapted rapidly to cater to the various demands of the community.

Additionally, small fixes such as the smoke grenades working properly are easy to propagate via a beta patching policy, whereas it would become confusing to release many 'hotfix' patches to address small stuff like that. It's probably better in the grand scheme of things to do "full" patches only every x-many months, leaving the beta stuff as an option for the 'hardcore' to use if they so desire. The process of using the beta patches is so simple - both from a server admin and a player's perspective - and the compatibility is so perfect currently, that there isn't much reason not to use them.

The beta patch policy that BIS has put into effect is probably one of the coolest changes to policy that they've ever done, to be quite frank about it. Once upon a time only select people had access to this stuff. Now, everyone has a shot at it, and everyone can provide their feedback. That's an attitude I love to see from BIS, and I think it'll pay off great dividends. I think it already has, really. The fact that we were able to go from "VON is broken" to "VON works!" in a single beta patch iteration, with it being pushed out to players as soon as it was done, and not having to be mercilessly tested (as it would need to be for a full patch), should be a pretty clear benefit.

Perhaps this would better illustrate it:

Old method: "Hey guys, just wait, the next patch is going to have working VON, it's sweet!"

Current method: "Hey guys, guess what? The latest beta patch, available (here), fixes VON! Everyone can try it out, it's sweet!"

I like the latter, personally.