In my data portability presentation, I always talk about services going away or changing. But even I hadn't really considered what happens when theres simply data lost. Ma.gnolia was a service I did use briefly between my switch from delicious to evernote and back to delicious. I had a ton of bookmarks on there but only really had 20 or so which were not on delicious or evernote. On top of that, I use a simple cron job to pull down my bookmarks every few weeks. However even this method isn't perfect as I sometimes have my laptop offline when the time comes around for the next backup. I really should move the cron job to my download machine which is always on and connected to the net.
Anyway I was lucky, I was reading stories earlier in the month from people who couldn't trust online services again with there data. I hope over time they will find ways of trusting services but I totally see the need for more services/apps which offer simple backup solutions. For example Conduit could be perfectly placed for this type usage, if there was more providers and generic hooks. The other solution is to simply have your data running through many services. One goes down and looses everything, another can be pulled upon to get the data back. Actually Ma.gonlia is using Friendfeed to recover some of its data, so it may sound slightly crazy but its already happening. Right now my microblogging activities are aggreagated over about 4 different services including twitter, identi.ca, Jaiku and Ping.fm. My RSS reading is still all on Newsgator but I'm planning a cron job for the APML (one of the things i'm missing from ma.gnolia) and OPML. Plus I have Newsgator offline clients on 2 phones, 1 ipod and 2 computers.