Is this a joke? I have Firefox with loads of tabs, Safari, Photoshop, Xcode, Mail, Playing a movie, BBEdit, and torrent all running at the same time, on my 2011 13-inch i5 with 4gb of ram. When I but the new machine this year, I might not even get the 8gb, it is really no necessary. I only want the new one for the battery.
I have a 2010 MBP17 8/512(aftermarket ssd) and a 2011 MBA13 i7/4/256, and it's amazing how much better than 8GB machine is. I got 8GB because of VMs, but now what I use a desktop box for most VM stuff, I still get much more consistent performance for Chrome/Firefox, Lightroom, etc. For editing RAW files or video, more RAM is also nice, as is fast disk. Xcode mostly seems to do fine in 4GB though.)
(I also have a late-2008 MBP15 4/500 for home theater/hooked up to my projector, and it's obviously far far sadder than the MBA, mainly due to the drive. Once it starts swapping, it's game over, whereas on an SSD, swapping just sort of sucks.)
I pretty much wouldn't buy a Mac with less than 8GB again. Certainly true in a year, so buying one today with 4GB cuts lifespan a lot. I tend to buy fairly loaded machines for anything built-in, then upgrade to max all the aftermarket stuff a bit later once prices have dropped, and keep machines for ~3-5 years in some capacity.
No, its not. I have a 13" MBP 2011 and I swapped out the 4GB RAM with 8GB and noticed a huge difference. Earlier it used to beachball all the time but its much better now. Right now, Chrome alone is using 3.5GB+ memory.
Have you tried running a hardware test? You shouldn't get beach balls at all while waiting for something. They're not called spinning balls of death for nothing.
Doing a clean reinstall (not just restoring image) seemed to solve similar problems for me in the past; I probably could have debugged exactly what files were messed up, but a fresh install was a whole lot easier. I've had this happen a few times, particularly on systems which were 10.7 and then various 10.7 and 10.8 Developer Previews finally updated to release 10.8.
I'm having a weird problem right now where iMessage doesn't work on an iCloud account for a system which had iMessage installed separately (on what, 10.7? I forget), then upgraded. Presumably the same fix will work.
What is "loads of tabs"? Just curious as my experience with Firefox and many tabs was rather displeasing. Tab Mix Plus helped with usability, but the responsiveness was not great. This has been in the single digit versions though.
