Currently my favorite approach leverages the Round Robin Record Assignment app from Force Labs available on the AppExchange. The app is configured to manage the assignment of cases, but with a little tweaking of the triggers and the class, you can get it to manage leads as well.We added a couple of custom fields and work flows and VIOLA!!! You have your custom Round Robin Lead Assignment application that you can also manage from from your iPhone or Blackberry (and you know Android is coming next month).
The app, as we have customized it, allows us to add members (users) to the assignment group with a couple of clicks and removed them by simply setting their Active status in the Assignment Group to "false". You can also schedule the removal and re-insertion of members from and into the round robin cycle. This is useful when a rep is going on vacation. All you have to do is enter the date that he/she will be leaving and the date of their return. The work flows will take care of changing their active status in the assignment group to false and back to true on their scheduled return date.
Before if you wanted to individually assign leads to 20 reps using round robin, segmenting them as Hot and Warm, you would have to create 1 assignment rule entry per user per queue (Hot and Warm queue). That's 40. With this app, you can now do this with 2 rule entries and let the Assignment Group membership handle the actual assignment.Thank you Force Labs.
Here's a link to the setup and configuration of the app.
Round Robin Record Assignment - Setup and Configuration.
Below I have included a screenshot of the Assignment Group screen. You can see the number of users (20) in the group. and you can see what Queues are associated with the group. In this case there is only one. By looking at the Assignment Group Members related list, you can see the members and their statuses, the last assignment made in the group to the member, as well as any scheduled dales for exiting and re-entering the assignment group.