There are more than a few discussion forums available for people looking for SolidWorks specific conversations online. Here’s the list of all the forums I use (in alphabetical order), with a quick personal statement of my opinions. Feel free to add to my commentary, disagree, or even mention others.Â
3DCADForums – This website has forums for AutoCAD, CATIA, Inventor, IronCAD, ProE, Solid Edge, SolidWorks, UG/NX, VX CAD/CAM, and 3D Studio Max.  Membership (free) is required to participate in discussions. It lists all topics in order of most recent activity. This forum seems to attract very little attention from SolidWorks users. I find that the site loads very slowly. Additionally, advertisement placement is very distracting. I do not recommend this site.
comp.cad.solidworks (link is via Google Groups) – This forum is accessible via many usenet readers. It is SolidWorks specific.  Many SolidWorks users frequent this group.  It is not uncommon to find new postings occuring hourly. Depending on access method, topics are listed in order of topic creation. The forum  environment can range from extremely helpful to extremely hostile. I cannot recommend this forum to new users. It is OK for experienced users who have a thick skin.
ENG-TIPS SolidWorks 3D CAD products Forum – Eng-tips is a vast site with a diverse selection of topics covering many different Engineering related fields.  It requires membership (free) to participate in its discussions. It lists topics by most recent activity. It is heavily moderated. This can be beneficial at times, but also detrimental at other times. Contact between members is limited to the website itself. Email addresses are banned. It does have some advertisements, but they are not intrusive. The site owners send out infrequent spammish emails (one email a few times a year). Because of these facts, this site has many detractors. However, in my mind, the advantages outweigh the disadvantages on most days. There are many knowledgeable contributors that frequent the site.  Additionally, I have found this site to be a good source for API assistance. One further advantage is that there are a bunch of other engineering related forums that make this a convenient one-stop location for those who have interests outside of SolidWorks.    Activity occurs on a nearly hourly basis. I recommend this forum, with the caveat that one should expect its strict rules to be heavily enforced.
mCADForums – This website has forums for AutoCAD, Inventor, Mechanical Desktop, SolidWorks, Alibre, Pro/E, Solid Edge, GrafiCalc, many user groups, and some general engineering discussions. It lists topics by most recent activity. Membership (free) is required to participate in discussions. It seems to attract very little attention from SolidWorks users. However, activity may be increasing. It has advertisements that are slightly distracting. I do not recommend this site to SolidWorks users solely based on the fact that activity is light.
Part 2 of this article will list other sites, including consideration of the main SolidWorks forum.