More of a typo than a spello in the sense that P is next to O on the qwerty keyboard so gets hit occasionally, especially in the tense rush of online gaming.
Similar to zomg, because z is next to the shift key and they were going for OMG.
Apparently due to intermittent shifting of 1 into an exclamation point, occasionally yielding multiple 1s, which can look like a random eleven, which is humorous to skip to directly.
Similar to zomg, because z is next to the shift key and they were going for OMG.