I've used titantv.com guide for several months now and I think the layout is excellent as well as the features offered. I really like the colored categories and filters, it makes perusing through the guide much easier. IMO it's one of the best online guides there is and now even better with the shobot tie-in.
A recent addition is a little gray/white "S" symbol beside a listing where you can click on that and (after you sign up with Shobot) you can set up a season pass
on your Tivo for that series with your default season pass settings. You also receive a confirmation email both from Tivo and Shobot.
At this time you only have a selection to set a season pass through the guide but I just received an email from the co-founder of shobot who said that later this month you will be able to record any show and choose between a season pass or individual recording. They are working on changes at this time.
To view/setup your free Titantv account go to www.titantv.com
Once you set up your account and configure the settings the way you want, choose something you want to record that has a gray/red "S" symbol in that tv listing and click on that. First time users will need to choose the system you're on (Tivo=other) and then you set up an email address/password. As part of the process you will be 'linked' to your Tivo account so if you have more than one receiver on your account you can choose which one you want to record to. It still takes awhile before the recording shows up in your todo list but I think that has to do with when your Tivo calls home to the mothership.
More information on the shobot service here: www.shobot.tv
*note* I have no affiliation with titantv.com or shobot.tv, just a happy user.