First, welcome to the world of Xlobby.
Others will most likely chime in, but here's my $0.02 (this is solely on the free version):
Are you planning on using the free version of xlobby (which can be downloaded from my link below, or from Sharp's google site), or were you planning on purchasing Calrad equipment with the hopes to get a paid copy? If the latter, then you will have to discuss with Calrad. The free version doesn't require any hardware outside your HTPC to get running...unless you want to add some sort of automation or something.
Realize that xlobby is not responsible for the playback of media, that is left to independent external software. What xlobby does is interfaces this software to its media type via databases/catagories. So in looking at your statement:
I use it for HD DVR, Gaming, Blu-Ray playback (PDVD), netflix instant watch, and my music collection (this one is super unimportant).
If you have the external software that can either be controlled via command line, or by windows messaging, then it can be controlled via xlobby. My current HTPC, I use xlobby which interfaces with DVB Dream for TV/PVR duties, Zoomplayer for movies and videos, winamp for music playback, and eventually either PDVD, or MPC for HD playback. Again, xlobby up front supplies the "eye-candy", while it controls all the other software in the background.
1. Considering that I have a pretty stright forward usage for my HTPC, is there an advantage in using xlobby instead of Vista Media Center?
Now this all depends on what your looking for. If your into tweaking, then xlobby, or mediaportal, or meedios are great for that. I give xlobby the advantage as it has a great skinning engine, and leaves all the media tweaking to the individual player software.
Now if you want something up and running quick, then VMC is most likely the choice to use. But be aware that if you want to perform certain things, then you may be limited in its abilities. HD DVR playback may be one of them.
2. How easy is it to install/configure?
This is a difficult question to answer as everyones requirements are different. If you go with the included skin, or some other simple skin like Buddabing's KISS, or Colby's Blueskin, then you can get something running pretty quick. Also it depends on if you have to setup your external software to run within xlobby. You may have to configure screens, events and buttons to perform particular functions. Configuration difficulties is purely on the user and what he/she wants out of the setup.
3. When should/can I do the install/configuation? (I am doing a new OS install and want to know if there is a better time then others to put xlobby in
Before installing xlobby, you have to have .NET 2 installed, or it won't work. It should also work with .NET 3. Other than that requirement, you can install at any point after installing the OS. I think also for Vista, you have to install xlobby in the root c:/, and not in Program Files.
4. Are there/where are tutorials on installation and config?
If you download the free version from Sharp's site, then he has a small tutorial on how to install the free version. On my xlobby site (link in my signature), I have a document section where there are some tutorials and skinning documents. Sharp also has a pretty similar section on his google site as well. Some of Buddabing's skins also include excellent tutorials on setting up xlobby (most noticably the KISS skin). Though these are geared towards his skins, they have some excellent info on general xlobby setup.
I really need to get a high WAF on this go around with the HTPC.
By no means do I want to deter you from using xlobby. I think it is one of the best HTPC frontends around. Just realize that any third party software of this nature will take a little time to learn, and to configure for your own use. MP and Meedios will also fall into this category.
by Maximo on Wed Sep 03, 2008 1:59 pm 
that way you can play before doing it for real.