The current publicly available prerelease (p3) suffers from a very annoying altar bug that makes converting an altar as a non-lawful or being a pious chaotic practically impossible. This bug alone affects normal gameplay enough to turn some potential players away from the public prerelease and keep them playing 1.1.1 until the finished product comes out. Surely it's in everybody's interest to have more people playing the new versions, as it amps up the hype and results in more needed bug reports and feedback.
Here's a possible solution: make prerelease 5 publicly available. This would be easy enough to implement, it doesn't include any of the new races and classes so it still keeps the private prereleases exclusive, and it doesn't include any notorious crashing or gameplay altering bugs.
As an accompanying measure (and this is something Thomas hinted at at some point), private prerelease access could be opened up to new donors. There are plenty of people coming out of the woodwork who did not hear about the campaign in time or didn't have the financial resources during those two months who would love the opportunity to donate now in exchange for access to the prereleases.
What say you? I don't have commenting access to the Adom blog, so perhaps somebody could post a comment there and direct Thomas' attention to this thread.
Edit: correction as per Stingray1's post below.