TFA says, "A win for Apple, a win for us, and a win for our customers."
Basecamp appears be saying that the new implementation offers a better user experience.
The win for them is that they get to update their app instead of being booted from the app store.
I suppose if you've been sitting on the sidelines since 1971 to see if this whole "e-mail thing" was a fad or not, and currently don't have an email address, a 14 day trial with some rando address might be just what you're looking for. Now if only you had some one to email...