The end temperature of your meat is a matter of personal preference.  It is also a matter of health. 

However, to me the two most important things are:
1) To realize quality meat when you see it, and
2) Have a good relationship with your butcher, or at least know of a good local butcher shop.

Those two things will take care of most problems.

Think about it: top quality meat of almost any sort should be able to eaten raw.  I don’t do this myself, or suggest it, but from steak tartare to sushi, there is a long history of delicious raw meat in the world.  This is only possible when you feel in control of the provenance of the meat.

THE GRILLING MAN’S MASTER TEMPERATURE INDEX

ANYTHING GROUND
First off, learn how to grind your own meat.  This will help ensure that if you cook it rare or medium rare that it’s safer to consume.  It also brings you closer to your food and will increase your appreciation of a job well done.  If you are not going to grind your own meat, DO NOT shop on price alone.  Find a local butcher that does their own grinding on a daily basis.  You can even pick a piece of meat in the counter and ask for it to be ground on the spot.  Never store ground meat in your refrigerator for more than a day or two before using it.

Medium rare burger of any type: 140 degrees followed by five minutes of rest
Medium burger of any type: 150 degrees  followed by five minutes of rest
USDA suggested temperature: 160 degrees which will kill any bacteria in the meat

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BEEF, VEAL, AND LAMB
Beautiful rare beef (the baseline): 125 degrees
For non-roasts (i.e. New York Strip on the grill), best to remove at 125 degrees, followed by five minutes of rest.
For roasts (from top rounds to rib roasts, etc), remove at 120 degrees, followed by ten minutes of rest.

Medium rare beef
Add five degrees to the above formulas (130 for non-roasts/125 for roasts)

Medium beef
Add ten degrees to the above formulas (135 for non-roasts/130 for roasts)

Beyond medium
Really, honestly, what are you thinking?

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PORK
The outdated idea that you have cook the hell out of pork in order to render it safe for human consumption has finally been proven false; it’s even acknowledged by the USDA (see the New York Times article for details).

Perfect medium pork: 145 degrees
For roasts, go a bit higher, like 150 followed by a ten minute rest (the fat needs to break down a bit more in these larger cuts, and slow cooking a pork shoulder is a different thing entirely).  These temperatures will end up with pink and juicy meat, and will ensure that even the leanest cuts are not only edible but enjoyable.

Note for Pork Shoulder and Pork Ribs
For the preparation of shoulders and ribs, the internal temperature is not the issue … don’t even worry about sticking a thermometer into the meat.  Rather, it’s the external temperature that should be held between 200 and 225 degrees over a long period.  This temp allows for the slow breaking down of the fibers and the fat, and the resulting magic of heavenly pork.

Note: please read my warnings regarding meat temperatures