We've been discussing this in chat; the change to stop distributing the newsletter at the same time seems terrible. It's unclear if the newsletter covers questions last week (i.e. Sunday-Saturday) or over the last 7 days. If it's the former then everyone gets the same newsletter, but some people get it Monday and some people get it Friday -- why are these people forced to wait four days for something they could read right now? If it's the latter, there's no concept of "the second SO newsletter in August" -- everyone gets a slightly different newsletter depending on the moment they were e-mailed.
Either way, this seems far worse than everyone getting the same newsletter at the same time. If some people are getting a bunch of newsletters at once and can't read them all, they can move them into a separate folder and come back to them later. I've never heard of a site changing the way it delivers e-mail so that people get messages in their inbox at a slower rate -- no e-mail client requires you to read an incoming message immediately or lose it. It's like only showing one question per minute on the SO homepage because some people read slow