I have an MXD with multiple SDE connections. When one of those (outside my immediate control and unfortunately on a server that is in bad shape and to be replaced relatively soon...) goes down, in v9, I would get a 'drawing error' pop up in the lower right hand corner, but could continue with what I was doing in my MXD. Now in v10, losing this data source totally kills my map. I get "not responding" and I have to manually kill ArcMap. This is a royal pain when editing because all my edits get lost (and yes, I save often, but still...).
The other problem is if I try to launch an MXD that has a broken sde connection in it, it will hang and not open. In the past, it would open but with the Red ! - now it does not do this, it just gives me "not responding" and never opens. This also kills connections via ArcReader...
Please fix this!!! Thank you!