Now that 60p/50p is an option interlaced footage does seem like a bad idea. 60i/50i is still perfectly fine for many situations and handles fast motion alot better than 24p, but the more choice we have, the better - in my books, anyway.
Since moving to HD I've found myself de-interlacing my 50i footage alot more. It get's rid of some of the nasty interlace artefacts that can appear espescially when scaling/changing speed, and since I'm down-converting for DVD anyway the resolution loss from de-interlacing is barely noticable.
I'm too timid to start shooting entirely in progressive. I shoot mainly weddings and I just can't imagine not having the ability to effectively slow footage down in post. With my GH1 I use the 25p but only when I know I won't want to slow the shots down.
When 1080p50 becomes mainstream then progressive will be the only way for me too.