I have TW Roadrunner. My modem from them is about 4 years old (well, it might be older, I've had it 4 years). Would a new modem be "better" in terms of improving speed or quality on streaming movies? I use a 3 year old apple timecapsule as my router, if that matters.
Well, that is the $130 question, and that is what I am hoping for. I'll let you know, my modem is supposed to be activated by today or tomorrow. According to some searching I've done, (here for example), it might very well improve the stability and speed of your connection IF you are connected to a DOCSIS 3.0 backbone. Of course if your router is crap too that might just negate any benefits anyway. (I use a Linksys E300 router with Tomato firmware -- you can really monitor and tune your traffic with QOS, built in VPN for travel, really cool stuff.)
I have standard internet which is supposed to be 10mbps down/1mbps up, and my major problem is that I never get above above 500kbps up. This is really painful when trying to back up my files off site to skydrive, etc. so I really have nothing to lose taking the gamble, and I should be able to notice any improvement from the docsis 3 modem.