Since the beginning of March I've been running an experiment of my own between Google Maps' Traffic feature and Traffic.com. I wanted to see how well Google's traffic information compared to Traffic.com for the Philadelphia area. George, left a comment yesterday asking about the comparison, so after two weeks of using each side by side, here's my review.
I live in Limerick, PA which is north west of the heart of downtown Philly and I drive about 25 miles to Plymouth Meeting, PA. I take Rt. 422 east to the Schuylkill (Skoo-kull) Expressway (I-76) east to the Blue Route (I-476) north. Most days it takes me about 35-40 minutes to get to work. There are alternate ways to get to the office, but I only use them when Rt. 422 is really backed up, since the alternate way consists of two lane roads and a lot of stop lights (it is about 4 miles less in distance though).
If I had relied solely on Google Maps' Traffic, I'd be cursing every time Rt. 422 backs up. Google Maps' Traffic fails miserably where Traffic.com tells me exactly where its backing up, jammed or slowed. The map above shows the route via Google Maps. I highlighted my route in blue, and an alternate in purple, and then pointed out where it normally backs up in red, where Google consistently fails to point out.
Traffic.com however, shows both "Backed Up" and "Slowed" traffic areas, and updates that information consistently. The great thing about Traffic.com, is that you can get reports emailed to you for your drives (I've got them set for both going to and coming from work), and additionally, if your route experiences a "jammed factor" beyond a certain threshold, you can be emailed as well. Traffic.com also marks off where there's accidents, issues or construction - Google doesn't do that at all.
I don't know where Google gets its information from for its traffic reporting. Where ever they do, at least for the Philly area, leaves a lot to be desired. Traffic.com, hands down is the superior service here. Of course Traffic.com has a very extensive network built up here, complete with digital drive information -- and you even seen their own vehicles on occasion, driving through the traffic during your drives.
Google Maps Traffic might be good for the occasional traveler to the "City of Brotherly Love", but its sorely lacking for the every day commutes in area. For now at least, I'm sticking with Traffic.com - it keeps my blood pressure down!