The War of 1812 is a venerable senior citizen in the wargame world, having been more or less continuously in print since 1973. Unlike it's slightly older sister game, Quebec 1759, the War of 1812 has seen some significant rules changes over the years, although nothing so drastic as to change the character of the game.
That character is a game that's an excellent introductory level wargame with quite a bit of scope for bluff and strategy, although kept tense by a fairly high luck factor. Unlike most Columbia block games, which mitigate the luck factor through a high volume of rolls that tend to make things even out, War of 1812 is subject to wild swings of fortune. It's not uncommon for a critical battle that may determine the status of a large swath of territory to be battled out between a single pair of blocks. When you're just rolling a few dice there's less chances for luck to even out. While the odds still favor a strength 4 block against a strength 2 block, all it takes is one "snake eyes" to suddenly change it into a free-for-all.
The biggest change in the newest (2008) edition of the game is in the naval rules, which scrap the unique system that's been used in the game virtually unchanged for three-and-a-half decades in favor of a new system that's consistent with the combat system used in all the other Columbia games. Now fleets are built a step at a time and each step fires at "F1" (which means it hits on a roll of a 1) in a simultaneous exchange of broadsides. Gone are the two-step building process, distinction between "operational" and "nonoperational" ships and deciding the battle with one grand roll of the dice.
A smaller, although still significant change in the naval rules, provides fleets an option to escape capture if an enemy army attacks its port. Under the old rule the fleet's fate depended entirely on the outcome of the battle, but now the ships can attempt to sortie while the ground forces cover them. Of course, a proper tactic is to make sure a powerful fleet is already on the lake waiting for the escapees, but they at least have a hope of doing some damage.
Changes in the land game are more incremental. The dragoons introduced in the last major revision have now been expanded in number and now fight at F2 all the time, making them more powerful. Their strength of 2 keeps them from being too dominant.
A new branch is introduced, with each side having a couple of artillery units in their draw pool. These also fight at F2 and have a CV of up to 3, so they provide a bit of punch these small armies. Rolling hits on a 1 or a 2 is a big edge when there are so few dice being rolled.
Each of the army blocks has an individual name, now, which is also a change and should make PBeM easier. The game also distinguishes between militia and regular troops. This has no game effect for the Anglo-Canadians but a significant impact on American operations, in a Good New/Bad News way.
The Good News is that now the American player knows ahead of time which of his pieces are militiamen who may balk at crossing the border into Canada. The Bad News is that now there's a 50% chance the militia will hew closely to their military obligation to serve only in the US. Under the old rules there was a 1/6 chance for any US unit to refuse to cross.
It doesn't appear that these changes will change game strategy much and they have the virtue of being a bit more realistic at a very low cost in complexity. Indeed, I think the new naval rules are simpler than the old ones, so the net change may very will be nil.