Some pretty good tips from Allen. If he kept his posts to things he knows about (ie travel logistics) instead of things he has apparently no knowledge of (the business of running casinos), I think most people would have no quibbles with him. In any case, my 2 cents on some of his tips..
Carrying cash on board planes: There was a thread about this somewhere last spring on 2+2. In general, anything less than $10K is probably fine. I wouldn't carry it on my person since you have to remove all items from your pockets to go through the screener. Just put it in your carry on and make sure you stay with your carry on at all times other than when it goes through the x-ray. I have had my carry-on checked many times because I travel with a computer and lots of wires. I have never been asked about large sums of money I might be carrying, particularly when traveling to places like Vegas. I suppose its possible you might be asked by an over-zealous TSA agent. To my knowledge there is nothing illegal about carrying less than $10K on a plane so as long as you give a reasonable answer, there's absolutely no reason this should cause you any difficulty. Checking with the TSA website from time to time (or your own country's authorities) is always prudent to see if any laws have changed. Of course, if you can wire the money ahead and not incur a cost, this might be a good alternative.
Checking Baggage: I agree that in general checking baggage should be avoided. But if you're going anywhere for more than a week, this might not be possible, and points people have maid about carry-on restrictions are valid. Also, if you're travelling through multiple airports, lugging around garment bags or other carry-ons can be a pain, especially if you're stuck for an extended time due to a lay-over or flight delay. Sometimes its nice to just get rid of most of your stuff and be unencumbered. Waiting at your destination for you bags can be annoying, but to be honest, the amount of time it takes to get off a plane these days, you usually don't wait too long. An, IMO, places like Vegas seem to do a better job than others at getting you your bags in a reasonable amount of time. I do agree that checked baggage could causes issues making changes to your travel plans. There have been times when my connecting flight was seriously delayed and an earlier flight ON THE SAME airline was available... however my checked bag would not be transferred. I hope that technological advancements will make this sort of situation less common, but it is a real concern today. Of course, the ultimate solution is to win a bunch of money playing poker and hire a personal assistant who will fly ahead of you and buy you a new wardrobe for your trip so you don't have to pack
As for locking your bag, I disagree with Allen. You can lock your bag... you just should use a TSA-lock, otherwise, if they chose your bag for inspection, they will cut your lock off. If you don't care about the cost of the lock, this could be ok. While TSA locks will not prevent officials from looking in your bag if it is suspicious or if it has been selected randomly, the lock will prevent baggage handlers or others from accessing your bag. I wouldn't necessarily put large sums of money or other valuables in a checked bag, but there's no reason you can't lock it.
As for flying on Southwest, I'm pretty sure their first-come-first choose method of boarding was implemented to maximize the fullness of their flights as opposed to their stated reason of increasing the efficiency of the boarding process. I have never found their process to be at all efficient. That being said, I don't think you really need to pay the extra $10, or whatever to avoid the dreaded middle seat. As long as you check in the day before as opposed to when you get to the airport, you ought to be able to get a place within the "B" boarding group. Anything is possible, but I've taken probably something like 50 Southwest flights and have never been stuck with a middle seat when I checked in the day before. If you absolutely need to sit in the front of the plane, you will need to pay more.