Being a newbie myself, and having the same question 4 days ago after I finished my first batch, I went in search of answers. A lot of this hobby is experimentation and preference, which is what appealed to me. However, I do like to know the reasoning behind things and when there is time to do one thing and a time to do another.
My best answer is to refer to you "Palmers Brew Bible" (
http://www.howtobrew.com/section1/chapter9-1.html). I read through this online version and he answered a lot of my questions. In general, it sounds like it doesn't really matter if you strain the wort before going into fermentation. However, there is the potential for off-flavors to occur if you leave the beer on the trub for long periods of time. Refer to the link, but basically as the yeast finish processing the main sugars (attenuation), and then go back for the byproducts (conditioning), eventually they may end up scavenging the trub which gives the undesirable off flavors. Again, its about the length of exposure and I think that may vary between beer style and what the brewer is looking for. It also depends on whether you plan on using a secondary as well.
Anyways, hope this helps. There are a couple other links below that were references Palmer used. For you reading pleasure. Enjoy!
http://brewingtechniques.com/library/backissues/issue1.4/barchet.html
http://brewingtechniques.com/library/backissues/issue2.2/barchet.html