Somewhat surprisingly, most cable and fiber internet providers are delivering speeds close to what they claim, but DSL continues to overpromise and underdeliver. The cable and fiber companies have actually improved overall since last year, although there are still some who can’t provide advertised speeds to all of their customers all of the time.
As someone with DSL, I have first hand knowledge of the shortfall. DSL speeds vary depending on how far away from the Central Office (CO) you are. We’re not that far, as the crow flies, but the convoluted path our line takes has resulted in a much longer distance. Previously, we got around 4.6 Mbps down but were paying for more. So we complained and they set us up with two connections bonded through a special DSL modem. But instead of getting 2x (9.2 Mbps) we have 7.6 Mbps. It’s better, obviously, and streaming video from Netflix and Hulu have improved, but it’s certainly not what I expected. This is the pinnacle for us, there’s no way to get any better. We’re hoping for fiber to appear in our neighborhood but we’re not holding our breath.