One poster on a forum kind of stepped in it by citing that (allow me to paraphrase)...."ALL guns made after the GCA of 1968 are drop safe and dropping a gun is nothing to worry about"
Now without getting into the folly of that statement regarding handguns of domestic manufacture, lets look at a couple of things.
Even if a gun IS drop safe, a lot of people will try to catch that gun and that's when they blow hole in an unintended object/person. Guns such as your Glock, M&P, etc have that nice little trigger safety that works great until you try to catch a falling gun, as you are clutching with your hand and stand a pretty good chance of getting a digit inside the trigger guard and breaking a couple of firearms safety rules.
NEVER TRY TO CATCH A FALLING GUN!
Second, sometimes manufacturers just don't get things right, take into account the previous recalls on the Ruger SR9 and LCP
Ruger - LCP® Product Safety Warning and Recall NoticeSo, regardless of age, or newly incorporated whizbang safety implements, never count on a dropped gun to not go off, and in the event that you should drop a gun, never try to catch it.
Ruger has received a small number of reports from the field indicating that LCP pistols can discharge when dropped onto a hard surface with a round in the chamber. We are firmly committed to safety and would like to retrofit all older LCP Pistols. The retrofit involves installation of an upgraded hammer mechanism at no charge to the customer.
We have determined that some Ruger SR9 pistols manufactured between October 2007 and April 2008 can, under certain conditions, fire if dropped with their manual safeties in the "off" or "fire" position. The pistols will not fire if the manual safety is in the "on" or "safe" position.
We will retrofit all affected SR9 pistols (those with serial number 330-29999 or lower) with these parts at no charge to our customers. In order to ensure correct fitting, the new parts must be installed at our Ruger factory in Prescott, Arizona. We will remove the old parts and install the new trigger group promptly, at no charge, and will return the pistol to you. The old parts will not be returned.
Edited to add: If you're about to drop your gun into a lake etc. it may be worth catching and long guns are a different story...