Two Degree Spacing
The FCC now allows two degree spacing among satellites, so more satellites can fit in the allotted space. This spacing requires your dish to be aligned perfectly so that you do not pick up adjacent satellites. Some of these new adjacent satellites are much higher in power than the satellites currently in orbit and will cause interference more easily if your dish is not in compliance.
Digital v. Analog
Receivers respond differently to signal degradation in the digital domain than they did in the analog domain. With analog, you heard the signal get noisy before you lost it. In the digital domain, other than a "marginal" warning light, there may be no warning, audible or otherwise that you are about to lose the signal.