I can honestly say I didn't think about much when doing this boss, just the regular "get out of shit" worked well, and as a healer this fight is fairly easy. Because of this, this won't be a real strategy guide. I'll only mention the impressions I got from the fight because when I read the tactics for it I notice that the vast majority of them are stuff I never noticed or had to think about while doing the fight.
Is is Omnitron or Omnotron? People have been uncertain since the launch of Cata. Wowpedia is addin to the confusion by naming the article Omnotron Defense System and then call them Omnitron throughout the text.
What did I think about the differences between 25 man and 10 man? The fights are exactly the same, there's only more of it, just as in Wrath. Having 25 people run around does create some difficulties. Finding a good spot to stand when you need to spread out is alot more difficult for instance. On the other hand, people are expendable in a way they definitely aren't in 10 man. Actually I think I will elaborate more on this in a separate post, and especially when I've got more of a chance to test 25 man out for comparison.
Two things stood out to me while healing. Kiting the adds, which are green blobs like on Putricide, and moving out of fire. This says alot about the fight, since it is really straightforward and easy to do. Unlike in the fights I've done in 10 man so far, there wasn't much I had to think about beside healing. I know there are a couple of things someone has to interrupt and you had to keep a distance from one of the bosses for some reason, but none of these were important enough for me to remember, and we made it without deaths anyway. I don't know why Blizzard would make one fight that is so much easier than all the rest. The other fights we downed that evening - Halfus, Valiona & Theralion, Argaloth and Magmaw all felt pretty much like their 10 man counterparts. I've never tried ODS on 10 man, but I find it hard to believe that it would be much more difficult.
Mostly it felt like people were running around like blind hens. Finding a good spot to stand has always been more difficult, but I also got the impression that me failing for a second or three mattered alot less than it would in 10-man. And best of all, no one would notice as long as I didn't fail on something crucial (like interrupting some skill or move out of some death beam). This could be from the way my guildies played - ie not very organized - but hey it worked fine, at least for this boss. The lasting impression was that ODS was kind of like when I went to Kindergarten - people everywhere, running around, not knowing what the other did, but we still had a hell of a time.