Yes, VDL will work on laptops that meet or exceed the system requirements for VDL. Keep in mind that nearly everyone who uses VDL also runs in in conjunction with a notation program (Sibelius or Finale) or a DAW. So it's also important to note the system requirements for other software you intend to run simultaneously with VDL.
A few notes for laptop users:
To help battery life, most laptop computers ship standard with slower hard drives (usually 5400RPM, sometimes even slower). This can definitely affect performance on scores that play back many voices simultaneously. We recommend laptop users to opt for 7200RPM hard drives for best performance.
Another thing to consider with portable computers is the soundcard (audio interface). Current Macintosh portables such as the MacBook, MacBook Pro, and MacBook Air work great right out of the box due to their reliable CoreAudio drivers. Windows PC laptops however, may require you to consider purchasing a higher quality soundcard more accustomed to pro audio. Windows users should be sure to use a soundcard that comes with an ASIO driver. For more information on soundcards, check out this article about soundcards.
While 1GB RAM is sufficient to launch the VDL player and load some sounds, we recommend 2GB RAM (or more) for best results with larger scores. It's important to keep in mind that the RAM in your computer is running the operating system, your notation software, VDL, and anything else you might have open.