More better (since you get a newline at the end of the above)
string.trimWhiteSpace(sys.unixShellCommand("osascript -e '(path to pictures folder) as string'"))

The list of possible “magic” folders in AppleScript

Get multiple folder paths in one swell foop

osascript -e '{(path to pictures folder) as string, (path to applications folder) as string}'

returns a comma-separated list.

• applications folder
• documents folder
• favorites folder
• home folder
• library folder
• movies folder
• music folder
• pictures folder
• public folder
• shared documents
• shared documents folder
• sites folder
• utilities folder

From the Applescript folks…

An additional tip about “path to”: you don’t need to wait for us to add an
explicit enumeration, since it can also take any four-character string that’s a
FindFolder selector. Get your hands on a copy of Folders.h (part of the Master
Interfaces) and go nuts.

Look here

/Developer/SDKs/MacOSX10.4u.sdk/Developer/Headers/CFMCarbon/CarbonCore/Folders.h

The “open” command knows what it is.

in photoFanThread.script

if system.environment.ismac {
  Â«webbrowser.launchMacBrowser () // [001]
  // [001] use the system utility
  sys.unixShellCommand("open " + homeurl) // [001]
};
photoFanSuite.init ();
system.temp.photoFan.flStarted = true;
// [001] we have already "opened" the URL on a Mac
// [001] don't do it again
if not system.environment.ismac {
  webbrowser.openurl (homeurl)
};
webbrowser.bringtofront ();
photoFanSuite.background.everyHour () //do a scan on startup