Grow two extra fingers!
Sorry, I couldn't resist it....
On a more serious note, the fastest keyboard users I've ever come across were data prep operators on ye olde 80-column card punches. They used somewhat specialised QWERTY keyboards and the layout didn't seem to slow them down at all.
No need to learn Dvorak according to XKCD (and more here).
I also remember reading in The Design of Everyday Things that QWERTY actually does quite a good job or spreading the commonly used letters across your fingers and whilst the Dvorak keyboard is a little better than QWERTY the benefits aren't significant enough to justify making the change. (If I can find my copy I'll try and put up an exact quote.)
You don't need to learn Dvorak. I can type 600+ Chars/minute on a querty pad, no problem.
The key is: Repetition, repetition, repetition. What you're doing while you learn typing is creating new 'highways' straight form your brain's spelling center through your spine to your fingers.
Hence, a good typist will spell a word in his mind, and his fingers 'automatically' type those characters because there's a 10 lane highway from his brain to his fingers. In your case, it's a modest 3 lane highway.
Practice, practice, practice. Good training for if you already know how to type : www.play4traffic.com
There's also loads of typing tutor programs available online, but the key is repetition and persistance.
My native language is Dutch, so in english it's not as good. I tried the test you gave:
317 points, so you achieved position 194065 of 2927935 on the ranking list
You type 476 characters per minute
You have 80 correct words and you have 4 wrong words
I've read, that secretaries can speed up to around 600 characters per minute!
Have I to learn dvorak?
Did the secretaries you read about use Dvorak? I find it nicer, but mainly switched as it forced me to learn to touch type rather than for the 10% improvement it's supposed to give to professional typists.
As with all things: practice makes perfect. Making posts on StackOverflow is a start :)
Unless if you want to win typing contests, a Qwerty or Azerty keyboard will work just fine.
I also took the test and reached 371 characters with one mistake. However, for programming, I would not see this as a bad result. I'm more worried about how to use tools like Intellisense and code templates better to speed up my coding. The jedi coding demo shows that you can get much higher gains that way than by doubling your typing speed.
I removed all of the key caps from my IBM Model-M. Since I can't see the letters, I was forced to learn their positions and type without looking at the keys other than to initially orient my hands. When you're not able to take shortcuts, you tend to learn very quickly.
Why?
Why do you want to type more quickly? I seldom find that my fingers or typing speed are the issue when it comes to software development. Sure I have a fair speed, but programming is about SO much more than typing speed. I've been using a QUERTY keyboard since about 1983 so I guess repetition helps.
But learning to hold back on typing and thinking about what it is you're about to do is far more valuable IMHO.
Having said that, I would expect any developer to be able to type reasonably quickly using most fingers, or at least more than their two index fingers ;)
This game taught me a few years back.
I can now type fairly quickly without looking at the keyboard. You need to learn to use the correct hand position. Then you must have good discipline and only use the correct finger to type the correct letters. I even went so far as to delete correct chars typed with the wrong finger.
It takes time, and you will almost definitely go slower before you go faster, but it is worth it.
Practice is the best way to get faster. I've found TypeRacer to be a fun and easily accessible game. Using it I quickly got from around 55 words per minute to over 70.