I've installed 2.5 on a test domain on our Linux box. Much improved performance and UI. Also, file uploads are handled much better, with a media manager feature. Control over thumbnail size and better handling of large files. So far, a win.
"OU Campus Developers: There's still time to build and submit your working gadgets to our 2014 Gadget Challenge for a chance to win free registration + travel reimbursement to OUTC15! Learn more about building gadgets in OU Campus by…"
"We just finished our institution-wide, procurement, redesign, development, migration and launch our our university's public web presence with T4 Site Manager. I've been intimately involved in the entire process.