Tvheadend

Yes, but make sure you keep the list view, which is far superior in a Web interface, IMHO. With the list view, you scroll with the scroll wheel, you can see more of a day's programmes because you're looking at one channel at a time and you don't get tiny truncated programme titles and descriptions like you do with grid views - the Sky example you pointed to suffers massively from this last point.

I would say that the only issue I have with the EPG list view in tvheadend is that the default column widths are "wrong" (some columns always truncate text for me, such as the Episode, Start and Duration columns (the critical one here is Start - I can never see the start time because the day of the week is in long format like Saturday instead of Sat).

This is further ecxaberated that if I resize the columns, they're not remembered if I either reload the page or restart the browser. Fix this and I'll be a happy bunny :-) Apologies for going a bit off-topic here, but I'd rather list views were improved first than grid views added (the latter of which sounds much more work to me).

Personally I find the list view a bit hard to navigate. Could it be split such that the left column allows you to select channel (including an entry for "All Channels".

Regarding grid views, I do agree that the truncation is a tricky problem. For the web interface it could be eased by using tool-tips. I also wonder if it make it better by changing the orientation, i.e. columns are channels and rows are the time.
That would allow the scroll wheel to move through time. It also provides more flexibility in column width because you don't need to fit into an arbitrary time span.

Just a couple of thoughts.
And my first comment, I'm a new user of tvheadend and it's working great so far. Many thanks for the efforts.