(We have our special guest Imam, brother Calif Namazifard bringing his unchallenged knowlege of Islam to the readers of this blog)
The word "al-Taqiyya" literally means: "Concealing or disguising one's beliefs, convictions, ideas, feelings, opinions, and/or strategies at a time of imminent danger, whether now or later in time, to save oneself from physical and/or mental injury." A one-word translation would be "dissimulation."
The creators of the above wiki page have been taqiyed to some extent as they have been convinced that this is an exclusivly "Shia" doctrine, when in fact it is not.
Ibn Kathir is perhaps the most respected Sunni quranic commentator of all time, and his tasfir sates: "believers are allowed to show friendship to the disbelievers outwardly, but never inwardly.
For instance, Al-Bukhari recorded that Abu Ad-Darda' said, "We smile in the face of some people although our hearts curse them. Al-Bukhari said that Al-Hasan said, "The Tuqyah is allowed until the Day of Resurrection."
The provision to use Taqiya (deception) on a chat forum like this is permissable in the sense that it is used to protect Muslims from "mental injury" or to protect Islam from defamation. Based on the rule:
"Reconciliatory Taqiyah. This type of Taqiyah is done when a person intends to reconcile with the other side or when he intends to soften their hearts. This kind of Taqiyah is permissible but not obligatory." (from the above referenced link), or on the more liberal definition here: “The criterion for it is that every praiseworthy objective in Sacred Law that cannot be brought about without lying is permissible to lie for if the objective is permissible, and obligatory to lie for if the objective is obligatory.”
In other words, when debating Muslims it is very important to keep in mind that any friendlyness towards you may be hiding secret hatred - as this is what Islam teaches Muslims to do.
Furthermore, a Muslim may determine it is OK to lie to you or even feel obligated to lie, if the objective of the lie is "praiswwrothy" - ie something like converting you to Islam or defending arguments against Islam.
Don't get me wrong here, I am not saying that all Muslims are liars, because not all Muslims strictly adhere to the teachings of Islam, I am just saying that in lieu of these teachings, don't take everything a Muslim tells you at face value, no matter how pious he seems, since he my be interpreting Islam to include lies of a "pious nature".