Hope this helps somebody: I've been using the registry-based enumeration in my scripts (as suggested by some of the answers above), but have found that it does not properly enumerate 64-bit software when run on Windows 10 x64 via SCCM (which uses a 32-bit client). Found something like this to be the most straightforward solution in my particular case:
Function Get-Programs($Bits) {
$Result = @()
$Output = (reg query HKLM\Software\Microsoft\Windows\CurrentVersion\Uninstall /reg:$Bits /s)
Foreach ($Line in $Output) {
If ($Line -match '^\s+DisplayName\s+REG_SZ\s+(.+?)$') {
$Result += New-Object PSObject -Property @{
DisplayName = $matches[1];
Bits = "$($Bits)-bit";
}
}
}
$Result
}
$Software = Get-Programs 32
$Software += Get-Programs 64
Realize this is a little too Perl-ish in a bad way, but all other alternatives I've seen involved insanity with wrapper scripts and similar clever-clever solutions, and this seems a little more human.
P.S. Trying really hard to refrain from dumping a ton of salt on Microsoft here for making an absolutely trivial thing next to impossible. I.e., enumerating all MS Office versions in use on a network is a task to make a grown man weep.