I suppose redoing the effects shots of Star Trek is partially marketing driven as a means to make the HD transfer of Star Trek more saleable.
I am in the camp of doing it as long as the originally film effects are still available. I'm surprised to make that statememt, but it's like colorizing black and white films.
As far as reframing the shots for 1.78, I recently got a plasma TV, and I watch the Star Trek DVD's in zoom mode so it fills the screen. Perhaps the zoom is too much, but there are times the tops of actors heads are cut off, things like that show that it might be tough to re-frame.
There was a webpage that was up for a long time that has the test reels made in the late 1990's of The Doomsday Machine effects shots. I have them downloaded and I tried to find the page to link to here. BUt the page is down. In looking at them, it shows two problems for redoing the effects.
1. The artist who did them took the liberty to re-design the Doomsday Machine. Due to the limitations of the software, or the artist, the new design didn't look anywhere as imaginative as originally filmed. The new shots were new angles and views. Interesting, but didn't add anything. It was cool at first, but in the end, they looked like CGI. The Enterprise that they did wasn't accurately recreated and the shading looked like CGI. A top artist today could do a better job, but the problem remains, will they be faithful to the original designs and shots.
2. The second problem is matching the shot grain and texture, the effects house did a terrific job for Star Trek The Motion Picture. But will modern CGI be "dumbed down" enough to match the filmed live action. Again, it could jump out at you and look out of place.
If CBS Paramount is doing it in-house and not via contracting a effects house, I hope CBS has a crack team in-house, they could be hacks.
I have no problem with a lot of the effects shots in TOS. Most of the time, they match the design ethic of the live action. By that I mean that in the first season, a lot of colored gels were used on the live action shots on the ship to add to the stylized feel of the show. Shots of the Klingon Battle cruisers were shot similarly with a green gel in the third season.
Granted, there are some bad effects shots in the first season, but that is part of the flavor of what the series has endeared on the public for the past 40 years. In a way, it's like adding 20" rims on a 60's musclecar, it works sometimes, but most of the time it looks like you tried too hard to modernize a classic and visually doesn't work.
edit: I see Peter THX posted before I did. The clips I have downloaded that are test reels were down by Digistream. The artists were Rich Heierling, Doug Johnson, Jon Peoples. They did a pretty impressive job at the time, but it's not as realisitc or fits in very well to the live action, with all respects to Digistream. If the webpage comes back on line, I'll try to post a link, it's very interesting to see their work. Maybe CBS shut this site down.
I did find a site with Youtube videos that has the Darren Dochterman footage. His try is better then the Digistream efforts I mention above, but it's still jarring in my opinion and a bit over the top. He also messed with the transporter effect. This links to that page, click on the fourth video down from the top: http://www.videosift...r trek&tag=true
And here is his site: http://trekenhanced.com/