Might as well throw my opinion into the ring. Briefly, of course, I don't have time to engage in Text Wars: The Quotes strike back!
I essentially think the whole debate on whether something that benefits you is still altruism is misguided. All living creatures are distinguished by their desire to fulfill a function, for whatever reason. But of course, if we reduce everything to functions, we realize the limitations of being a evolutionary derived creature, always wanting to benefit oneself and avoid harm. The selfishness argument eventually says there is no way to act without fulfilling a wish or want of yours, which place all emotions on the same level. Since they are not equal, and since we want a discussion of one, it is wise to define the emotion.
So it depends on the definition of altruism. Under the official definitions of the two words that represent altruism; disinterested "not gaining a material advantage" and selfless "putting another's needs above your own". So from this, altruism is working when you do not benefit yourself in a physical or material way, and one where the intent is not to serve oneself but to serve others. Although one serves oneself by serving others, this is not the intent, and is to do good to the other, despite personal material or physical loss or damage; and differentiates a act of compassion from say, amusement.