Anolog or Digital scanner? - Trains Magazine

Analog scanners won't do digital.  Digital scanners can do analog.

If you're buying new, go digital (something like the computer mantra - buy the biggest, baddest computer you can afford).

The first narrowbanding mandate (2013) will probably have railroads staying with analog, but not necessarily.

The next narrowbanding mandate after that will probably force a move to digital.

Public safety agencies are also moving to digital, and especially to trunking.  If you're interested in that realm, consider that when making your purchase.  I do think you'll find most digital-capable scanners are trunking scanners.