Yep, love this plugin!!
Previously I just used Vista's built in Video browser. I had all my movies together along with a small 200x150 jpg in a folder called movies (eg Transformers.avi, Transformers.jpg, Terminator.avi, Terminator.jpg etc).
It all worked well and looked ok, but as my collection grew it started getting a bit clunky and hard to find what I wanted to watch.
I needed a way to sort by many different attributes, filter by genre, or find other movies by a particular actor. Media Browser does all that and MUCH more + looks amazing.
The only problem. Each of my avi's weren't in their own folder & I'm funny when it comes to leaving stuff like building metadata to automation.
So I started 3 days ago manually setting this up and can see light at the end of the tunnel.
If it helps anyone else heres how I did it;
In lots of 50 I quickly noted down the name of each film. On my NON HTPC computer I installed Media Center Master and Metabrowser. I wanted MCM for its access to imdb instead of tmdb (imdb is better for rating, actors & description). I set them both to watch a temporary movies folder and also set up an ImagesByName folder and pointed them both to it. I downloaded a very small avi file (some quick vid of a flame flickering I think) and chucked it into a new folder in the movies folder (there needs to be a movie file in there to work). Then one by one of the list I renamed that folder to the name of the movie. When you run MCM it sees that folder and does its search. It will also include along with its imdb data, a cover and backdrop from tmdb. Then I closed that and ran Metabrowser. Now the only reason for doing this is to check if there are other covers or backdrops available that I like better - and there quite often was. So untick all the other fields so they are not updated (don't worry, it remembers what you have unticked for the next movie). ps. also tell Metabrowser to rename the folder for you too.
After that you will have a folder named eg Transformers (2007), and inside you will have your dummy avi, mymovies.xml, folder.jpg & backdrop.jpg. Copy the folder to a flash drive to later transfer to the HTPC (once copied you can delete the avi). Clear out the original working folder (leaving only the avi) and rename ready for the next movie. repeat... and repeat... and repeat...

Once you are through your first lot, on your HTPC rename your old movies folder to movies_OLD. And create a new movies folder. Move all the movie-titled folders you have created into the new movies folder and start dragging all your avi files into their corresponding movie-titled folder.
Now you have a perfectly set up movie folder, with a folder for each movie containing all the necessary files. The reason for doing this is those files are your backup that Media Browser will use to make its own database cache without going to the internet itself. So if you ever need to delete Media Browsers cache, it can quickly build it again from your files. I could imagine nothing worse than letting Media Browser do its own job on 200 odd avi files. What a mess you would end with.
Sounds like heaps of work if you want to do it this way, but if you are patient and good with computers you can knock em off bit by bit. The reward at the end is sweet.