Just another idea..
How about a link/filter possibility on the user home node which shows links to 'Nodes which I started which have been active (had a reply) in the last X days' - where X is configurable.
I know most people like to start out at the 'Newest Nodes' to see whats been going on, however I think thats too much information, I prefer to start at SoPW, Meditations and PMD. Then I look at nodes that I started to see if there have been answers recently. At the moment theres no way to automate that apart from adding them all to the personal nodelet, and removing them when I think there will be no more answers.
If everyone else does it differently than me, then I guess I'll live with it .)