Tasks was one of the most disappointing aspects of webOS. It just seemed that Palm broke from it's PDA roots in many ways, especially tasks.
There are several task solutions in the App Catalog and other sources. I tried RTM, Remember The Milk, for about a year. I paid the $25 for premium so I could use other clients, but I was never satisfied with it.
A month or two after going with RTM, I also bought PocketMirror from Chapura. It came with tasks, but I ignored it 'cause I already had RTM. I only used PocketMirror for notes, which worked great.
I was using Cloud Tasks to maintain my RTM tasks on my Pre, but it suddenly stopped working (when I launched it, it just would just hang). Cow Tasks never worked.
So I went back to maintaining my tasks on Outlook and syncing with Pocketmirror, the way I had been doing for about 10 years with my PalmOS devices. I'm very happy with it.
So... long story short... I use PocketMirror with Outlook, and I'm very happy with it.
Hope that helps!