This week's book giveaway is in the OCMJEA forum. We're giving away four copies of OCM Java EE 6 Enterprise Architect Exam Guide and have Paul Allen & Joseph Bambara on-line! See this thread for details.
Yes, Hashtable was retrofitted to implement Map, so there is little to distinguish them, apart from Hashtable's methods all beign synchronized (this is like the difference between ArrayList and Vector). And this is not really useful -- if you want a proper threadsafe map, consider ConcurrentHashMap first.