Growing up in Silicon Valley and with computer engineer parents, I've tried learning to program a bunch of times. I've tried to learn Javascript, Python, Ruby (a Perl derivative), and HTML, and every single time I've given up in frustration. I don't want to be an engineer, so spending weeks or even months learning the basics of a language before being able to do anything was definitely not appealing.
Then, one day, I stumble unto a problem and I try to use AHK to solve it, and *BAM*; I'm hooked. In only a few minutes, I was able to use it to create an actual program (not the typical "Hello World") and solve a longstanding problem (typing em dashes). Admittedly, AHK can be pretty complex, and certainly can't be mastered in an afternoon, but, and this is an important but, it lets you create useful little programs right from the start. Maybe the traditional languages like Python can do that, but certainly that isn't their focus. Their focus is on building big programs like BitTorrent, Miro, Battlefield 2, Civ 4, etc. That's great, but I'm not trying to create the next Windows or the next Halo.
In contrast, AHK's focus is on building tiny yet disproportionately useful little programs (should they even be called programs? applets may be a better name) with a focus on simplicity, functionality, practicality, and cleverness. And for most of us, this is exactly what we need.
Now, I'm not suggesting that future programmers (as in those who want to code for a living) start with AHK. IMHO they would be best served with Python or Ruby. However, for the amateur programmer, there is nothing better. Leave the big languages for those who want to solve big problems.
A note on AutoIt: AutoIt is AHK's primary competitor but I've never tried it myself. I chose to learn AHK because of its better managing of hotkeys and its greater simplicity. AHK and AutoIt have a bad history with each other and a lot of users from both camps are blindly partisan; I'm not. Only you can judge what's the best language for you. It's like arguing what the best spoken language is.