To a lot of Twihards/tards/azis, the sparkly meadow scene is OMG SOOOO IMPRTNT!!!! and needs to happen. Technically speaking, the meadow scene does not need to happen, nor does anything else in the series, thereby removing the series from existence, and saving the future of literature. Unfortunately, they do happen, and literature suffers for it. One could argue that in the context of the series, the sparkling in the meadow scene could be considered important. However, it could have been done a lot better (and less chagrin-inducingly). For instance, couldn't she have made it so the vampires begin to die or experience extreme pain when entering sunlight, like normal vampires do? Of course, that would give the Meyerpires *gasp* FLAWS!!!! We couldn't have that, now could we?
BUT, ZOMG, YOU'RE FORGETING THE DREAM! Edit
No, we're not. Yes, the meadow scene is the scene she saw in her dream, which is what inspired
Failight Twilight. So yes, I can see why she felt it HAD to be in there. Plotwise though, all it does is drum into our heads that Edward is HAWT (something that had already been quite well established), and very fast (something we knew from the van incident). Oh yes, we find out he sparkles.
Besides, there are other ways to express that Edward is super hot/strong/sparkly/etc. The meadow is not necessary, period. The fact that SMeyer also based a scene of her book off her inspirational wet dream (urgh) shows that the book is esentially wish fulfillment, as with Bella's Mary-Sue-ism.
Notice: Dreams can also bring forth something GOOD like 'Dracula' from Bram Stoker, an actual VAMPIRE not some wussass sparklepants who's being emo all the time.... now I feel guilty comparing him to emo-people. Emo-people, sorry for comparing you all to some
abusive, psychotic stalker 'Vegetarian-ass-sparkles-in-the-sun'-pire.