Both. I've always been a fan of new items in a Zelda game, which is why I think items such as the whip, the beetle, and the gust bellows were great additions to the series. Each of them helped introduce innovative puzzles, as well provide new and interesting ways to solve them. They are also responsible for a lot of the series' innovative gameplay mechanics that involve proper timing and accuracy, as seen in SS [with the Beetle].
Conversely... It goes without saying that I'll always be a fan of the series' past equipment. I think it's neat that Nintendo continues to put a new spin on it that accentuates any new puzzle elements that each game has to offer. For example, its most recent usage, the boomerang has gained a plethora of new applications in both puzzle-solving and combat. It has been given the ability to hit multiple targets all at once (WW), and the ability hover in place for an extended period of time (FSA). With both of said uses came different applications that added a new dimension to an item that would otherwise be considered obsolete.
Although I admit that nostalgia comes into play as a major factor as well.
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At any rate, I think it is important that fans realize that with new puzzle and combat elements come new items and equipment. They go hand and hand. The day Nintendo stops introducing new equipment - or at the very least, putting a new spin on the old - is the day it stops introducing new, innovative puzzle elements and combat to the series. In other words, the end of Zelda series as we know it...