Wow! With one year in Las Vegas terms being the equivalent of several years for most "normal" cities, this question generated an answer of such epic proportions that we're going to run it over the course of two days, so we don't boggle your minds.
Still, you're in luck, since the current writer's first visit to Vegas coincided with your father's last, so I took a trip down memory lane, aided in no small part by the annual Report Card that the LVA crew has compiled for our members-only newsletter every January, since 1995. In it, we summarize all the key closures, openings, and other significant changes that have occurred in the previous 12 months, with a preview of what's on the drawing board for the future, so that helped jog the old memory a little.
As an aside, before we get down to business here, it's been a blast remembering some of the projects that didn't come to fruition, including Stupak's Titanic resort, Brad Pitt and George Clooney's idea for a casino with a dress code (they'd been watching -- or starring in -- too many old movies), a proposed collaboration between the former Hilton and BET to open a casino aimed exclusively at African-American visitors, plus all the plans for London-, Elvis-, San Francisco-, James Bond-, Harley Davidson-, and sports-themed casinos, to name just a few pipe dreams that never made it off the drawing board.
We were also amused to read that 1997 appears to have been the first time a plan for a major sports stadium was proposed. That one's still on that drawing board, 15 years and many incarnations and entrepreneurs later (see QoD 6/14/12).
In terms of a broad overview, here's a general heads-up you could give your dad, if he wants it; if not, just let it all greet him as a big surprise.
Since his last visit, the Strip continued to experience a massive boom until the whole global crash hit us right between the eyes, so he'll be amazed by how many totally new megaresorts -- and even a "metaresort," in CityCenter -- have been added to the Strip skyline. The casualties like Fontainebleau, which never made it to completion, will be a strange sight to him, no doubt.
As far as the general vibe goes, your father probably experienced the misguided "kid-friendly" experiment of the late '80s, which he'll no doubt be relieved to hear was abandoned, but will instead find a city that caters much more to the sexy young-adult crowd, with all the nightclubs, pool parties, party pits, etc. that this entails these days. He'll likely find Las Vegas louder and more casual (to put it at its politest) since his last experience. The proliferation of smut peddlers and the like, who both hassle and litter, is another less-than-welcome development, primarily on the Strip. Just keep walking.
Downtown was really in the doldrums until pretty recently, so the regeneration of the Fremont Street area, and the growth of a credible Arts District, is one of the more positive changes your father might like to take in. Fremont Street itself has cleaned up its act somewhat and added outdoor bars and seating at several venues, plus a new zipline attraction that's a blast. Fremont East, on the other side of Las Vegas Blvd., is now a buzzing nightlife hub, awash with diverse cool bars and a growing number of good and affordable restaurants (check out Le Thai if you're down there).
The diversification of the economy may well come as a shock -- from the current writer's recollection, it was still pretty much still all about gambling back in 1997, so the explosion of high-end restaurants with their "celebrity" chefs, shopping malls, and additional non-casino attractions, is a significant change from back then that's worth noting. Perhaps in the area of dining more than any other, in fact, Las Vegas has really changed its image, and he'll find more diversity and better quality than he could have dreamed of back in '97. The classic 24-hour casino coffee shop is almost a thing of the past, with many having closed or cut their hours, but the upside to this is a much-improved late-night dining scene, where you're not stuck with a choice of ham 'n eggs or biscuits 'n gravy if you get the munchies after midnight, but can still find bargain eats aplenty, especially if you're willing to venture off the Strip to local strip malls. (A copy of Eating Las Vegas: the 50 Essential Restaurants might well come in handy, if you feel like exploring the all-new dining scene with your father.)
Other specifics we all tend to take for granted now, but which were shockers at the time, include the advent of coinless TITO slots and video poker machines (will he miss those buckets of coins?), much tighter rules on smoking (although they've been relaxed somewhat of late), and just the general expansion of the city, both in terms of new properties, and of the population itself. Las Vegas is a lot more expensive than it used to be, but there are still plenty of deals to be had for the savvy traveler, and this site, together with our sister site couponsinvegas.com, constitute the primo places for finding the best current offers and inside tips for getting the most out of your dollars.
So, that's the current writer's take on what's happened here since '97. Tomorrow, we'll follow up with the specifics that occurred to us in terms of major closures, openings, and trends, so be sure to tune in for a trip down memory lane.