There is still some rebanding going on that may make some obsolete but the big deciding factor is what going on in your AO and if they have any plans to change systems in the near future.
I moved in 2008 and now am in a digital trunking area so my analog trunking scanner can't do the local stuff, time to sell it I suppose.

The national interoperability plans specify digital trunking so if you aren't in a digital area yet eventually you will be.
It's only a matter of time * money. (lots of money)

When you get your first digital capable radio expect a very, very steep learning curve on using it.

I've just started looking at the new digital trunking scanners. The limited offerings that are suitable for use in my area are in the $450-$500 range. It's been many years since I purchased my current scanners so I'm wondering if the current pricing includes an early adopter premium like other electronic equipment does.

Radio Shack was selling the Pro-106 and Pro-197 scanners for $300 (list $500) just before Christmas.

They had huge demand at that price. (they misunderstood the market!)

They are excellent scanners.

They replaced the Pro-96 and Pro-2096 which are still very good digital scanners though they will suffer if rebanding to the 700Mhz range happens in your area.

Digital scanners are always going to be more $, partly due to licensing requirements for the decoding software. Thats why you see 500 digital and 200 analog when there is very little difference in them otherwise.

Yes, the $500-ish price range that most of the Digital Scanners seem to have, makes me hesitant to take the plunge.

Does anyone know if these "national interoperability plans" will also involve some sort of encryption or "scrambling" of the communications? I would sure hate to spend the bucks for a digital scanner, and find out that it quickly becomes useless because the various agencies also start to use encryption that would "lock out" civilians.

RadioReference has discussions in depth.

There is a modulation scheme called ProVoice that's not decodable by hobbyist scanners.

And sometimes some agencies encrypt everything.

In Colorado, so far, only some tactical channels are routinely encrypted. And ProVoice hasn't worked out well so it's been turned off where tried here.

But it's always a risk.
OTOH it's also a risk that the encryption on the system won't work for the users either.

I use my scanners twice daily for the commute so it's well worth the $$ to stay on top of things.

Heard the big grassfires near Boulder paged out last week (for instance)

Good advice... I will do some more digging around at RadioReference. Yesterday was my first visit there; it looked like there was a ton of information there.

Right now, I am leaning toward a "basic" scanner to start with; maybe the Uniden BC92XLT. From what I can determine so far, that unit should work well in my area.

Radio Shack is reported to be selling the Pro-96 digital trunking scanner for < $200 in store.

It's been the workhorse among Colo scanner fans for 2 years. Pretty good price though it's no longer the current model.

Apparently, no. Here in Bucks County we're on a Motorola Astro Digital Trunked System, 500 Mhz, and while radio prices have come down a bit, a walkie-talkie is still over $2,000, and scanners that can pick up Bucks County are still $500, and have been for about 5 years. I don't know why this isn't coming down, I'll suspect that there's some kind of licensing royalty involved, as this would explain the lack of price drop.

As far as a national radio plan - not going to happen in the next 5 years or so, maybe not ever. The 700 Mhz "D" block auction fell apart, NYC isn't playing along with a national radio system, etc. etc.