There are always annoying pop-ups on the Flash (in-browser) streams, and you will regularly see ones that tell you that you are missing a certain plug-in to watch the stream and 'click here' to download. Avoid it - it's malware. You don't need to install anything to watch Flash streams, and following these links will just install some malware on your system. The pop-up boxes will have a tiny (almost invisible) X to close it, which you often have to wait 30 seconds for, or hunt around the screen looking for it.
If you go to http://www.wiziwig.tv/ they have links to streams that are either Flash, Sopcast or Acestream. The latter is worth installing (http://acestream.org/) if you have a decent enough internet connection, because they are high-quality streams with no annoying pop-ups or ads, although they are usually only available when it is the only game on at the time because it's on Sky. If you're looking for Saints v Wigan for instance, at 3pm on a saturday when there are 6-7 other games on then you'll have to settle for the Flash ones. The only downside with Acestream is the commentary will usually be in Ukranian or something like that.
All allegedly, of course