LiquidPlanner touts itself as “a revolution in project management.” That’s probably overstating the case somewhat (there are a lot of project management applications in the world), but it does offer a sophisticated feature set, including some things that I haven’t seen in other online project management tools. If you’re feeling constrained by the features of whatever tool you’re using, then this one is worth a look.
The biggest selling point of LiquidPlanner is that they do ranged estimation and probabilistic scheduling. That is, instead of specifying that each task on your Gantt Chart (yes, they provide Gantt charts – right there they should be able to take some business from BaseCamp with its relentless refusal to implement this feature) takes an exact amount of time, you can supply a range. So the developer responsible for implementing a feature can say that it will take 3 to 5 days, instead of exactly 4. Then LiquidPlanner combines all these numbers to come up with a set of dates when your project will be done – and you can look at the curve for this to get a sense of your most likely delivery date, as well as what it’s safe to promise.
LiquidPlanner also tracks the evolution of estimates over time, allowing project managers to view the “glide cone” of the remaining tasks: if you don’t see the total work decreasing, and estimates becoming more precise, there’s a problem. While they’re not the only tool to offer this sort of functionality (http://www.fogcreek.com/FogBugz/ is the other one that I’m aware of), they’re the only one I know doing it in the context of full project management.
There are plenty of other features in LiquidPlanner besides their approach to estimating. They set projects up as a sort of social network, allowing you to invite people to a “project space” where your projects live. You can track tasks on as many levels as you like, and each task comes with wiki-like commenting. Assuming you can get your team to commit to the tool, you end up with a rich and searchable history of your project, with everything from task assignments to design documents in one place.
With all of this complexity comes a cost: despite the use of dashboards to pull together organized views of your projects, your pending actions, and so on, the user interface here is very busy, and the learning curve is likely to be steep for those unfamiliar with project management or unaccustomed to richly-linked web applications. Assuming you have the need and the discipline, though, I’d rate this as one of the more comprehensive online project management tools I’ve seen. Currently LiquidPlanner is in open beta, free for all to use. After the beta period ends (probably some time this fall, according to company representatives I spoke with), the price will rise to $24.95 per month per member of each project space, though single-member and educational use will continue to be free.