Well, here I'll give you some reasons why I think you should be playing Warmaster right now. I'll try and provide some examples to illustrate my points, and you can also see examples of game-play from the Battle Reports posted here.
1. Warmaster is a fantastic game. Principly, it's balanced, fast and tactical. The game is so good plently of folks play using cards rather than miniatures.
The balanced nature of the game means that there is no major power inbalance between armies. Magic, characters and monsters all play a role, but ultimately it is the application of the force of arms that usually carries the day. This enhances the tactical element of the game, and while bad dice may still cost you dearly, good strategy will usually carry the day.
When half of your army has been destoyed, the game is over. Your troops retire from the field. This means that you must carefully apply your strategy to breaking your opponents army - particularly attempting to have your strongest units fighting your opponents weakest where possible. This can lead to some interesting tactical manouvering.
Warmaster is fast. Brigades (groupings of units) can move several times in one turn if you can issue them orders, and potentially could cross the table in a single round. Even armies of stout dwarves can move at alarming speeds.
Combat is also fast. Once combat is joined, you keep fighting until there's a draw, or someone quits. This means that a decisive cavalry charge can burst through enemy lines in a single turn. As combat is simultaneous, even units who face overwhelming odds can strike down their attackers.
Put simply; you count the number of attacks you have, roll to hit (almost always a 4+) and your opponent makes armour saves (if they have any). Whatever's left over, wounds the enemy. Superior troops have more attacks, better armour and more wounds. Cavalry, chariots and monsters are particularly powerful when charging, whilst infantry defends strongly.
3. While original Warmaster armies are now not easy to get - although you can still find them on auction sites like e-bay, there's a big range of third-party 10mm fantasy miniatures being made..
4. Miniatures are cool, and miniature miniatures are even cooler. The Warmaster range is great, and very well detailed. It features most of the armies available in Warhammer Fantasy Battle and a couple of others (Kislev or Araby anyone?). You can play truly epic battles, recreating the great moments in Warhammer World history, with liteally hundreds of soliders, and still be finished in a couple of hours.
If I've gone some way to convincing you, here are a couple of follow-up points for new generals;
1. Consider what style of army you might enjoy playing. Large horde armies like orcs and goblins or skaven are fun, but can be challenging to order around, while elite armies like elves or dwarves move well, but as their troops cost more, you will find that your opponent needs to destory less units to break your army. Generally High Elves are considered a good starting force, whilst Chaos mortals probably field the smallest armies (for the fiscally conservative).
2. Painting can be reasonably quick and easy. Particularly if you use foundation/base colours and washes. Generally, unless you're particulalry detail focussed, you should be able to knock off an army in far less time than a Warhammer Fantasy battle equivalent.
3. Bring lots of dice, perferably of different colours. The reasons will become clear once you start playing.