I have a nearly identical configuration, except for mine has the antiglare, and had the same goals as you when I started out. Here's my answers, hope they help!
1.) 128GB should be plenty. I have a 128GB Crucial C300 SSD as my boot drive, and I have a ton of applications (already) including rather heavy ones like Final Cut Pro X, Aperture, Motion, and MS Office. I also keep my current FCPx project on the SSD, that one right now is ~18GB. I have 29 GB free currently.
2.) That's precisely what I did, except I used Lion Internet Recovery. It worked perfectly for me, the entire restore process took about an hour.
2b) If it's brand new, you shouldn't have to - the installer will do that for you. If not, in Lion Internet Recovery you have the ability to use Utilities (there will be a menu for it) and open Disk Utility to format it. Works like a charm.
3.) I used the MCE Optibay adapter and was very pleased at the completeness of the kit, instructions, and included tools. Granted I already know how to do it, and have the tools, but I thought "wow, this is great for those who don't know this stuff" when I was doing it. It's as easy as formatting and partitioning the drive using Disk Utility after it's installed. Just use Spotlight to search for it.
4.) Need? Excellent question that has many answers. Summary: it helps. I have it on both my MBP and my white MacBook, on the latter when I enabled it I noticed a rather significant increase. That machine has a Intel X-25M G2 SSD, which does have garbage collection, but TRIM definitely helped. Most modern SSD's have built in garbage collection that reportedly does a very good job, but I've always went the TRIM route. If you Google for "enable TRIM Lion" you'll run across very good howtos on the method behind the madness.
Again I just - in the past two weeks - did the same thing with the same machine and am beyond pleased with the result. Insanely fast laptop that's also a serious workhorse with the additional storage. I'm very sure you'll be quite happy with it, I know I am.
So, if anyone can answer the following questions, I would be forever grateful to you for making my life so much easier.
1) I won't ask which SSD is the best, though I still haven't decided between Samsung 830 or Crucial m4, but if I want to install OSX Lion, Windows 7, Steam + a few games (probably just Skyrim and one or two other games max) as well as an application or two, like iTunes, Skype and Microsoft Office, is 128GB enough or should I go for the 256GB drive?
2) When installing this SSD, can I just unbox the brand new machine, open it up, take out HDD, put in SSD and boot it up with Lion recovery CD in there, or do I need to do something special to format the SSD first?
2b) If I do need to format the drive, how do I do this?
3) What's the best accessory to get to replace the optical drive with the HDD and how do I set it up to be storage for music/movies and other nonessential applications? Can it be split so some applications install on the HDD and others on the SSD?
4) Do I need TRIM and how do I make it work so it doesn't mess everything up?
I think this encompasses all the questions that are currently making my head swim and I can't seem to find any direct answers for. I hope someone here can help me out. Many thanks!
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the better question is why would you want something that spins and vibrates put in a place that has no vibration dampening?
FWIW I have my 750GB 7200rpm stock disk in a MCE Optibay Adapter and I notice no vibration or noise, and I work the thing pretty dang hard.