I can not emphasize enough that BOTH the bride and groom are equal partners in the wedding planning. In fact, your fiancee' should WANT you to be involved; after all you will be making other important decisions (purchasing a home/car/ having kids etc) together after you are married, right? If your fiancee (or more likely her family/friends) want to limit your involvement in the wedding planning consider this a pretty good indication of how your marriage will operate. If she is more concerned about pleasing them and not at all concerned about your feelings/desires then be warned that rough roads may be ahead...

My recent wedding was completely a 50/50 affair. I had input into everything and we made every major decision together, despite the little detail that I was working out of state for 2 months and only returned 2 weeks before the wedding. And, amazingly enough, there was much less stress involved than in my first wedding where I had practically no input.