Fastbond wasn't legal, so yes, it was essentially serving the same purpose. The difference between the two is a bit odd. Fastbond is much, much more explosive, but if you did play with it unrestricted, you'd find that the awesome deck you were using based around Fastbond would work best if you could just draw one Fastbond and combo away with it, never drawing into your other three copies, as they are dead draws (playing them would actually hurt you).
Exploration, on the other hand, gets better with each one you draw. But playing any number of them is really just approaching the performance of one Fastbond without the damage aspect. I've seen some Vintage decks use both cards together in the same deck: four Explorations and one Fastbond. They don't have any synergy with each other, but the Explorations act as a supplement, since they're still accelerating mana production and card advantage (with Horn of Greed).