Choosing camera lens

[PamNY]

I'm getting a new Canon camera soon, and I'm considering this lens:

http://www.amazon.com/Canon-70-300mm...9530404&sr=8-1

I understand why prime lenses are better, but I'm not going to carry multiple lenses on my bike (or pay for them, but that's another story).

I like photographing birds, but have no ambitions other than putting them on Flickr.

I know this lens will have limitations in low light -- anything else I should think about?