How do I even begin to explain the concept of Jejemon that is currently terrorizing Manila? Let's see. Jejemon is a culture, a lifestyle confined to certain social brackets. It is derived from the phrase "jeje" which is a Frankensteined term for "hehe" (as in "Yes I admit I have a Justin Bieber CD, hehe!") + the word phenomeNON. Hence, Jejemon. It refers to a way of speaking but it is so encompassing a concept that it refers practically to a whole way of being.
In the jejemon culture, certain words have a way of evolving. Words like "hehe" mutates into the word "jeje", or "hello" into "eow!" and other such monstrosities. Jejemon must have started through texting. Manila is the texting capital of the world after all. So a simple "Kamusta ka na?" which is Filipino for "How are you?" becomes "mUztah na U?" with matching mix of small and large letters. The word "po" which is a respectful term in the Filipino language, becomes "PoWh." (See example above) It's a tragic concoction of awful spelling, terrible grammar and horrendous usage of both the English and Filipino language.
It must be very confusing for my non-Filipino friends, but let me go on.
This is the simplest way I know how to explain the jejemon culture: no self-respecting Filipino will want to be called a jejemon. Trust me.