One of the challenges with condensing workstation task sequences into a single task sequence is being able to distinguish between desktops and laptops as each typically has their own set of functions to perform when being imaged.  One of the best ways to determine this is by querying ChassisTypes in Win32_SystemEnclosure.  Unfortunately, ChassisTypes is an array value; the WQL that is used in the task sequence is limited to single values. 

To work with this, add the following vbscript to a Run Command Line task.  It creates a custom Task Sequence variable that can then be used to dynamically limit certain tasks to “desktops” and others to “laptops”.

‘==========================================================================
‘ NAME: SMSTSEnvChassisType.vbs

‘ AUTHOR: Nick Moseley, SCCM Administrator
‘ DATE  : 4/24/2009

‘ COMMENT: Script creates custom TS variable that can be used to distinguish
‘ between a desktop and a laptop for dynamically selecting which tasks
‘ to run in the sequence. Note that the echo statements are logged in SMSTS.log
‘==========================================================================

Full SMSTSEnvChassisType.vbs Code Here