Justin Achilli considers how modern technology could mess up a vampire's existence, while Russell Bailey adds how it could help.
With Requiem specifically, there's the issue of vampires blurring in mirrors and photos, something I'd likely houserule away, particularly for a game set in the UK where we have the most CCTV cameras per head of population of anywhere in Europe. (Or was it the world? Anyway, we have a lot of CCTV cameras.) So you aren't bending the Masquerade every time you step out of your haven, but could potentially break it and be caught clearly on video every time you do something vampiric. So you don't have to be careful just out walking, but you do have to be very careful out hunting.
(It also stops people using cameras as handheld vampire-detectors, as seen in Channel 4's Ultraviolet.)
It's a reminder of why so many horror films these days have that shot establishing that the characters' mobiles don't have any signal, and Let Me In was set in the 80s. And Paranormal Activity is made entirely out of security camera footage.