Depends on what you mean by trouble. Have I been caught unaware? No, since I found out about the change here on FT. However, having pushed it plenty of times in the past, I'm now finding myself killing extra time at the airport waiting for flights after being forced into an earlier return than I would have liked. Yes, it is only 30 minutes, but I value my time.
Hertz says this change in policy brings them in-line with the competition, which is partially true. However, I think bhatnasx's idea of half-day pricing would be a GREAT idea and a strong competitive advantage to encourage people to rent 1.5 days with Hertz vs. 2 days with the competition. Hertz doesn't really seem to care what we, the customers, want so I'd be surprised to see that happen.