Product Version = NetBeans IDE 8.1 RC2 (Build 201510122201)
Operating System = Linux version 3.13.0-66-generic running on amd64
Java; VM; Vendor = 1.8.0_51
Runtime = Java HotSpot(TM) 64-Bit Server VM 25.51-b03

Reproducibility: Happens every time

Context menu font size is noticeably smaller in 8.1 than it was in 8.0.  Screen shots coming shortly. 

In the screen shots, the 2 level menu (Folder, Java Class, ...) fonts are smaller, while on the first level menu "New" is bigger in 8.1 but "Find is smaller". 
The font size on the nodes in the Project View appears larger in 8.1 than 8.0.

I thought these were controlled by --fontsize in the netbeans.conf file. I have --fontsize 16 in both 8.0 and 8.1. 

8.0
netbeans_default_options="-J-XX:+UseG1GC -J-client -J-Xss2m -J-Xms32m -J-Xmx2500m -J-XX:PermSize=32m -J-XX:MaxPermSize=600m -J-Dapple.laf.useScreenMenuBar=true -J-Dapple.awt.graphics.UseQuartz=true -J-Dsun.java2d.noddraw=true -J-Dsun.java2d.dpiaware=true -J-Dsun.zip.disableMemoryMapping=true -J-Dsun.awt.disableMixing=true --fontsize 16 --cp:p /home/javalibs/jgoodies-looks-2.4.1/jgoodies-looks-2.4.1.jar --cp:p /home/javalibs/jgoodies-looks-2.4.1/lib/jgoodies-common-1.2.0.jar --laf Nimbus -J-Dswing.aatext=true -J-Dawt.useSystemAAFontSettings=lcd"

8.1
netbeans_default_options="-J-client -J-Xss2m -J-Xms32m -J-Xmx2500m -J-XX:PermSize=32m -J-XX:MaxPermSize=600m -J-Dapple.laf.useScreenMenuBar=true -J-Dapple.awt.graphics.UseQuartz=true -J-Dsun.java2d.noddraw=true -J-Dsun.java2d.dpiaware=true -J-Dsun.zip.disableMemoryMapping=true --fontsize 16 --cp:p /home/javalibs/jgoodies-looks-2.4.1/jgoodies-looks-2.4.1.jar --cp:p /home/javalibs/jgoodies-looks-2.4.1/lib/jgoodies-common-1.2.0.jar --laf Nimbus -J-Dswing.aatext=true -J-Dawt.useSystemAAFontSettings=lcd"