To venture a bold prediction: One of these days, a bus on Triangle Transit's Route 301, snaking through Cary between Research Triangle Park and downtown Raleigh, will actually be crowded.

Last week, on one of my occasional bus commutes, the bus that picked me up about 8:20 a.m. on Cary's Kilmayne Drive near the Big Lots store (the old Kroger) served by my count 18 riders the rest of the way into the city.

Now, that bus was still only half full when ridership peaked. But most, if not all, of the pairs of seats had a person in them. It had the feel of an urban bus -- in contrast to the typical pattern a couple or three years ago, when the driver would look at you sort of funny when you climbed on, as if to say, you mean you really intend to ride this thing?

Another sign that the price of gasoline these days is giving people sufficient heartburn that they're searching for commuting alternatives: The parking lot there by the bus stop in what used to be called the Kroger Plaza shopping center has become a popular park-and-ride site.

And why not? The trip into Raleigh or out to RTP costs a modest $2 -- less if you've bought a pass. Buses run during morning and evening drive times, every half-hour. The ride downtown dependably takes about 30 minutes, which isn't bad. You lose a few minutes but save on gas and a quota of aggravation (no dodging those dangerously snail-paced school buses on I-40).

This bus wends its way past Cary Towne Center, up Buck Jones Road and in on Western Boulevard, making it a good choice for a variety of people. There's always a contingent of N.C. State folks; others get off among office buildings along Wilmington Street (the route loops back after a stop just north of Martin). If ridership continues to swell -- Triangle Transit's overall figures show impressive growth -- someday the agency will need to do better than a patch of sidewalk at that downtown way point. Perhaps the city's adjacent Moore Square bus transit center could be expanded.

Or how about this? Someday, who knows exactly when but it will happen, commuter trains will stop in downtown Raleigh. There will be an opportunity for some kind of general-purpose transit hub. Look to Greensboro for an example, where the handsomely refurbished old Southern Railroad terminal has been conjoined with bus service.

For that matter, Raleigh's current Amtrak station could be bursting at the seams before long under the same kind of pressures that are persuading more local commuters to take the bus. Fact: More long-distance travelers are opting for the train.

Just last week the state announced a third mid-day train (or pair of trains) between Raleigh and Charlotte to meet rising demand. Purely in the realm of anecdote, when we drove to the station on Cabarrus Street one night last week to pick up a son who had caught the Silver Star down from Washington, we could barely find a place to park. And I've never seen so many folks getting on or off a train in Raleigh.

Stir all this evidence together, and it's hard not to conclude that we're on the cusp of a transportation sea change around here. What a timely piece of work, then, is the just-finished "vision plan" that offers comprehensive suggestions for the region's transit future.

The plan, worked out by a special commission, is truly a big-picture look at the role beefed-up bus and rail systems can and should play hereabouts. This has become "one of the most sprawling, auto-centric regions in the nation," the group says, and anyone who battles the traffic on our congested asphalt arteries would be hard-pressed to quibble.

Bus service between communities, to employment centers and on compact "circulator" routes would be ramped up to the point where thousands of additional residents would find it not only feasible but preferable to commuting by car.

Triangle Transit's plan for a Durham-to-Raleigh commuter rail line may have flopped because of low ridership estimates, but that was then, before pulling up to a gas pump became such a stomach-churning proposition. The new plan makes no bones about the importance of rail in the transit formula. Chapel Hill would be in the mix, as would outlying towns along the N.C. Railroad corridor that links Raleigh, Cary and Durham.

This is a plan whose rationale for mass transit investments is very pragmatic -- the economy and quality of life depend on it. Costs are highly competitive with new roadways.

And for the individual commuter, savings could be significant. As reported in the plan, AAA Carolinas computes the cost of owning and operating a small sedan driven 10,000 miles a year at $10,787. That equals a whole bunch of $2 bus tickets -- just do the math.