I Tracy, Steve: is a full time deck builder so he's probably more adept at the in's and out's than I am. I've been working with a deck builder for roughly a year (hard work for a guy that's really a programmer), but for what it's worth here's a breakdown on how I understand things based on where you stated you're at (laying decking boards -the part that we stand on-).
Once "we" get to the point of laying the decking, all of the rim and joists have been put into place, and the deck frame has been squared and secured with a brace (to keep the deck from moving side to side) and the posts (and/or beams) put into place. We then nail/screw every decking board off (excluding the outer rims). Once ALL the decking is down, we chalk a line along the outer rims, cut the decking, and adjust the rims as needed to insure a straight rim as they are nailed/screwed. Once the outer rims have been nailed/screwed the brace can be removed and there shouldn't be any wobble, in case there is we apply a diagonal 2x6 attached to "each" joist's underneath to eliminate the wobble (this is rare though).
Like I said, Steve: has done this a whole lot longer than I, and as I'm sure he will validate, codes vary from city to city, etc. But the bottom line is eliminating your wobble! If Steve: and I haven't answered your question, post back up with more specifics (I.E., posts in each corner, post and beam, etc.).