Aesthetics aside, one of the reasons that we advise you to put play structures in the back yard and in fenced, gated, private areas is primarily to avoid attendant liability. This is what is often called an "attractive nuisance" because it creates pockets of liability for a homeowner. By putting a play structure in your front yard, you invite the entire neighborhood and the children in the area to use your play structure with and without your knowledge. This is all fine and good until someone gets hurt, and as my insurance agent will tell you, there is no fury like the fury of a mother whose child got hurt at your home.
So unless you can afford a multi-million dollar liability policy, and are planning to purchase equipment that will withstand LOTS of use (commercial grade swings), or can ensure that no one will use the equipment without your knowledge or consent (usually a 6 foot locked fence is what is required for this), it's better to locate the equipment in the rear yard behind a fence where it is understood that entering would be trespassing.
Oh, and yes, putting a swingset in the front yard is also aestheticallly unappealing and may be in violation of your city's building codes, so check with the city before installing equipment in the front yard.
Allison James Estates & Homes