How vWorkspace deals with load balancing and if 3rd party solutions are still required for it.
There are different loadbalancing scenarios for the different vWorkspace pieces:
Connection Brokers: CBs are loadbalanced automatically when they are in the same farm. There's no "primary/secondary" or "active/inactive" broker. Random brokers are chosen automatically when various operations are requested. If broker is listed in vWorkspace Management console - it'll be used.
Terminal Servers: TSs are balanced semi-automatically and process can be influenced by creating a specific loadbalancing rules (Load balancing in vWorkspace Management console, assign rule to TS). When application is assigned to the list of TSs, broker choosing a least busy TS by checking the TS score. Score is dynamic and provided to brokers through the Quest Data Collector service. Score is calculated using WMI performance counters (disk, CPU, number or users, etc).
SQL database: this is a most important component and requires a high availability rather than balancing. Usually in production environments, vWorkspace SQL database is kept on the dedicated server or even on the SQL cluster. vWorkspace CB and TS machines are connecting to the SQL database using ODBC connector.
Secure-IT/Web-IT servers: these servers usually balanced using some hardware appliance (F5 or BigIP, Riverbed, Cisco ASA, etc) or Microsoft NLB. The most important thing here is something called "sticky assignment" or "session affinity". When user is connecting through such device, then user must be always directed to the same target server during the session (destination affinity). vWorkspace connection is a multi-step process so user should be directed to the same server (Secure-IT and/or Web-IT) while establishing a session.