Pay2Win can be defined as the ability to pay in order to gain a significant advantage over their opponents. Therefore normal players cannot hope to be on an even playing field without also paying.
Pay2SaveTime can be defined as the ability to pay in order to do what can normally be done without paying but in a shorter period of time. Therefore normal players can compete on an even playing field without paying. (But would require more time invested)
Pay2Win would consist of any of the following:
The ability to obtain gear/skills/etc not normally obtainable. Usually including increased stats/powers/etc. Removing basic mechanics from gameplay unless payed for. Usually increased raid/instance reuse times, or restricting of quests. (See SWTOR)
While at the same time nothing from the Pay2SaveTime would require you to pay in order to access. The same ultimate goal can be arrived purely though normal gameplay.
With this said, we aren't planning to go Pay2Win. We would very much like to limit the effects of normal players gameplay from any donation related items. I've just grown frustrated and the constant throwing of 'Pay2Win' around even in entirely non pay2win suggestions.
TL;DR