Actually, I think he has the right to say it. Apparently, a lot of others are experiencing the stalling/lagging issue with the Galaxy S. They pointed it to Samsung using the internal SD card instead of the internal NAND for their data which makes the phone lag. Why they did this is unknown but possibly a mistake on their part. The lagging only seems to happen when launching apps and going back to the home screen. Otherwise, it is perfect when playing games, media, watching movies, etc. Paul at Modaco made a fix specifically for it but you need to be rooted to do it:
http://android.modaco.com/content/samsung-galaxy-s-s-modaco-com/312298/got-the-stalling-problem-rooted-try-this/
Another fix was to replace the default TouchWiz 3.0 with another home launcher such as Launcher Pro which I am currently using on my phone and I think is miles beyond better than TouchWiz 3.0 (and probably the first thing I would remove once I get the a Galaxy S or Captivate). Additionally, the new firmware updates that just came out a few days ago supposedly took care of the stalling issues as well. Also, Paul has prebaked custom roms that you can use that have major modifications that speed up the phone even more as seen below:
http://www.youtube.com/watch?v=0RYugWwN4R4