I think the chant was actually "We are SPL" but it was indeed a memorable and significant moment. I would say that the majority of fans, or at least the ones being vocal on this forum, were dead against the idea of groundshare when it was first mooted (prior to us winning the league). There were lots of "stop this madness" threads, and people saying they'd rather support their local team in a lower league than have an SPL team playing in Aberdeen.
But when the league title was won, that attitude seemed to instantly go away, and the doubters seemed to realise that having earned our place in the top flight we should at least have a crack at it.
When we went up, even our own fans thought that, if we could stay up at all, we'd probably end up as one of those yo-yo sides at best. I doubt anyone would have expected that we'd be in the top flight for 9 of the next 10 seasons (make that 10 out of 11 now).