If you switch resolutions workspaces shown in multitasking view don't get resized if they exist already. New ones have the correct size. It's quite easy to reproduce. Just set your resolution to a lower one compared to that set automatically on login.
ProblemType: Bug
DistroRelease: elementary OS 0.3
Package: gala 0.1.0~r411+pkg28+r1~ubuntu0.3.1 [origin: LP-PPA-elementary-os-daily]
ProcVersionSignature: Ubuntu 3.13.0-34.60-generic 3.13.11.4
Uname: Linux 3.13.0-34-generic x86_64
NonfreeKernelModules: wl
ApportVersion: 2.14.1-0ubuntu3.3
Architecture: amd64
CrashDB: gala
CurrentDesktop: Pantheon
Date: Thu Aug 14 09:17:38 2014
EcryptfsInUse: Yes
GsettingsChanges:
InstallationDate: Installed on 2014-08-13 (0 days ago)
InstallationMedia: elementary OS 0.3 "Freya" - Daily amd64 (20140810)
SourcePackage: gala
UpgradeStatus: No upgrade log present (probably fresh install)
I have the same issue without changing the resolution. Actually the resolution is changing but not intentionally.
I'm using an additional big screen at work with my laptop and usually hibernate the machine at the end of the shift. If I reopen it at home with just the laptop screen, the desktop elements comes together with no problem but the multitasking view does not take the change into account. Since it remembers the old bigger resolution it becomes almost useless.