Pretty self-explanatory. If you want to know everything the budget traveller could ever need, cheapovegas.com is an awesome site. Breaks down hotel/casinos by cheapest eats, sleep, gaming, attractions and other deals. It also has a pretty nice selection of maps that are directly linked back to the properties themselves.
Although many of the changes in Las Vegas have slowed down due to the economy, there is still constant building down the strip. This site will allow you to view pics of the on-going status of all of the new mega-resorts going up (or blowing up) around the city. There is a fantastic color-coded map that's broken down by the umbrella resort companies. Again the map is all linked up and even shows all the proposed ideas for which proposals have been submitted. You can really see how Vegas will look in 10 years.
When you want updated reviews of new and existing properties vegastripping.com is the place to go. Although the layout is busy, the category breakdown and tools (including RSS feeds for deals) give quick access to a ton of information. Even includes a section on how to play some of the most common games.
For a bunch of quick-to-read updates on almost all of Vegas' hotels, restaurants, and shows, ratevegas.com has reviews going back to at least 2000. For most of the major properties there are several current reviews. They even boast an iPhone app that you can use to submit reviews while travelling up and down the strip... as though there wasn't anything better to do while in Vegas.
For all of you Social Media types, fivehundybymidnight.com has now done over 200 weekly podcasts all about the changes going on in Vegas and takes great pleasure in ripping the websites of some of the big resorts. They also drop some knowledge on recent entertainment announcements of shows and other news concerning construction and everything else going on. A great on-going resource to listen to if, like me, you love the city and want to keep up on the changes through earbuds instead of tedious reading.