My fiance and I are both in our early 60's and getting married for the third time. We want to surprise our friends and family at a backyard bbq this summer. The event will be informal and involve 50-60 guests, ribs & chicken,a raw bar, a solo guitar player, a keg of beer and lots of wine and champagne. We want it to be casual yet classy. Is it appropriate to surprise people with your wedding (we don't want anyone to bring gifts etc)? Or do you think our friends will be annoyed at being spoofed? Any suggestions for decorations that won't give the surprise away?