Most wireless options require software and or drivers to be installed in the laptop before they can be utilized in the system which can be cumbersome when somone drops in and does not have administrative rights on thier laptop to install software or devices. Wireless options also generally will not support full motion video but are ok with most power point material. Wired options have their pitfalls as well when is comes to limitations with the video card drivers and user error. Unfortunately there is no perfect solution for visiting laptops.
Bruce Sinclair Advanced Video DMC-E "Those who are most critical, often have no real skills themsevles"