I took an umpiring class this past Spring (2012), so I can offer what we were taught.
Regardless of whether a pitch is a strike or a ball, we were taught to wait a "tick" to be sure of what we've seen. If nothing else, this mindset helps one watch the pitch all the way into the glove.
If the call is a strike, one should rise from the slightly crouched stance, raise the right hand into a fist and pump it forward with authority and confidence while calling out 'HIKE'.
Why 'HIKE' and not 'STRIKE'? Simple, it's easier to call (especially for 7, 8, 9, or more innings), and it sounds close to the same.
The main point is to both call and signal the strike with authority. Oh, and swinging strikes are signaled, but not called out.
In addition, we're taught to make all strike calls, including strike three, where we're allowed a little bit of showmanship, while facing forward – not looking to the right.
Why? Well, home plate umpires in MLB, and I believe umpires in AAA along with umpires working certain special games, are the few who have the luxury of having another umpire on each of the bases. In the lower minor leagues, I believe there are typically only two base umpires, and in much, if not all, of amateur baseball, there are typically only two umpires total, one home plate ump, and one base ump who moves around the diamond depending on the number and position of runners on base. (Unfortunately, sometimes one umpire is unlucky enough to have his partner not show up, and he's force to make all the calls.)
If the call is a ball, one should not rise and not signal in any way – calling "ball" with authority, but usually not as much volume. At the amateur level, the call should be loud enough for the pitcher to hear it. Obviously, that goal becomes more difficult the larger the crowd is.
As a final note, remember that this is what we're taught. Once out of the classroom, personal style will naturally change some things. However, if one tries to be too much of a showman, it could degrade one's performance in the eyes of the coaches who submit the umpire game reports, which results in one being a showboat umpire in Little League (no offense meant to Little League umps – I've been one – I'm just saying that a poorly graded/ranked umpire won't even earn a chance to work Varsity HS games, much less move on to college games and beyond).
While this may not have answered the original question, I hope the insight is useful and/or enlightening.