When tabs are used in code text lines (which is what we're talking about here; not about switching controls or technical ascii standards or whatever other context), then the only purpose of them is to indend the codelines so they are better structured.
Doing this by spaces, preseving tab stops, or whatever else doesn't matter, even mono-spaced or variable spaced fonts doesn't matter, just as long as the codelines are indended. So I don't see no harm done in a simple replace of a tab character into a few spaces.
Code highlighting would be nice too, but that isn't going to happen anytime soon. Automatic enclosing with [noparse] and using the <pre> tag is going to be worse, since then we can not use any highlighting or formatting (eg: bold) ourselfs anymore, which is very important.
A simple replace of the tab character on the other hand is quite straightforward and easy to implement I think. And at least saves us from doing a manual ReplaceAll all the time when pasting code.
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