The IBM mainframes run on IBM proprietary software (OS/400 and others). And they are widely being replaced by Microsoft web-based solutions.
I`ll take IE 7 over FireFox 2, with it`s non-functional autocomplete, iframe swapping, and bass-ackwards event model any day! 
Ok, I don`t know crap about technology, so I won`t get too far into it except to say with Microsoft, I like the consistency. If I want to send an Excel file, I want the recipient to be able to open it and see what I wrote. I have no idea if other companies can make their software compatible with each other without violating patents, but if I could get any old spreadsheet program, and anyone in the world could open and view it, I`d be ok with it. May the best program win. However, I don`t think this is the case (correct me if I`m wrong) and I would gladly sacrifice a program with more capabilities if I could get one that is used consistently everywhere.
As far as the giants vs. the little guys, I feel that it is not a competition. Each is successful (or should be) in their own market. If I need just any old thing to get the job done, I`ll go to a big box store. If I need a special item that isn`t common, and fits my precise specifications, I`ll go to a smaller company or check online, or find an artisan who can create what I need.
The good thing about chains, big box stores and Microsoft is consistency. I can go anywhere in the US and find the same stuff. I don`t feel like this is a bad thing. I go on buisness trips every now and then for my day job, and if I need toothpaste, I don`t want to go all over the place looking for it. I want to go into a store that is familiar, even if I have never been in that town before.
Now... when I go shopping for souvenirs, that is different. I want something I can`t find at home. When I went to Wisconsin, I went to a small store that I had never heard of, and found a plethora of different kinds of cheese. I loaded up as much as I could fit in my suitcase and brought home some rarities that you just can`t find anywhere else. My ziplock baggies, however, came from Target, because it was close to my hotel, and it had what I needed at the time.
When people talk about Microsoft they say they innovate. I disagree, they see what is out there and copy it. The graphical front end operating systems is not a Microsoft innovation as some people may think, nor is it Apples. I have never seen anything that has been a Microsoft innovation. Innovations are fundamentally risky so its a turn off for large companies; they come from the small fast moving company or small group of people that see differently and create it. I look forward to Microsoft falling by the way side, it will allow openings and branches as yet unknown.
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