These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Game Breaker: Actually, mimicking the flu symptoms minus everything dangerous means that your disease will spread everywhere, including to Madagascar early on, giving you plenty of points to spend on fun things like heart failure. Giving your disease moisture I and heat I also helps a lot with infecting Madagascar.
Harsher in Hindsight: Every once in a while, countries will be hit by natural disasters and other issues, some of which have happened in Real Life (such as "New Zealand gets hit by earthquake").
The game as a whole could be considered Harsher now that there is an Ebola outbreak spreading around Africa and potentially to other countries throughout the world.
Hilarious in Hindsight: Madagascar really did SHUT DOWN EVERYTHING after the "zombie incident" in Florida where a man got high on bath salts and tried to eat a homeless man's face.
Memetic Badass: Thanks to this game, Madagascar will always be remembered as the sole area in the world that no epidemic can touch.
Madagascar and Peru, the only two areas in the game with only one way to infect them.
Western Europe was the original Pandemic's Madagascar. It had no airports or water sources. If you didn't hit it quickly, it would become the last bastion of civilization. Even worse, starting in Central Europe doesn't even assure you'll get it.
The Scrappy: Madagascar. Loved for the meme, but a damn nuisance when playing.
Broken Base: Which edition has the better artwork? Some prefer the more realistic and painterly style of the first edition, while others like the higher budget TV show-esque artwork of the second. The fact that On The Brink was the only expansion to be done in the style of the first, and all future expansions are done exclusively in the second has broken the base further.
Most Wonderful Sound: Winning the iOS adaptation transforms the classic map into a globe's normal blue-green colors, with soft, victorious music playing.