My experience so far w/ 12.04 is satisfactory. My aim is to transition thru the end of support for WinXP converting all my PCs and laptops, if Ubuntu will provide all the same functions.
Frankly I'm NOT interested in visual 3d transparency effects and I think Linux/Ubuntu is wasting development effort in that direction. I remember when Win Vista, Win7 transparency visual effects came out (I can't even remember what they called it) and it sent me out of the room laughing. I want stability and functional versatility. Trying to play catch-up with the GUI fashion fads is pointless. As everyone has noticed 3D is now out of fashion and the fisher-price toy eye-fone look is in. My advice is to develop a utilitarian desktop concept and stick with steady long term refinement The desktop overlapping window workspace metaphor is as classic and eternal as a "real life" chair and work table. When will the fashion touts start selling printer paper with cutesy rounded corners?
If you want t capture the disgruntled millions of steadfast WinXP users make WINE an integrated service of Ubuntu, and concentrate on adapting the work of thousands (tens of thousands?) of ex Windows applications developers. If you want to capture the eye-fone mentality, make android applets functional on Linux in a simulator.
My "updates available" inbox is flooded with developers tools, many of which have to do with Java or SQL development. My understanding from the WinXP malware standpoint is that many of these tools are simply unnecessary, superfluous or even dangerous for the typical non-coder end user. Why not include a check box or filter to exclude development tools from the update list, or at least describe them completely and color code them. For example we are warned of Java applets in browsers as a malware vector. Is this not as true in Linux as it is in Windows/OSX? Most of these daily updates are indecipherable to the average user. Yes we know the Linux community is disproportionately populated by programmers and scripting adepts.
What would I really prefer? A WinXP/Win7 GUI "clone" built on Linux. A stable GUI that doesn't change (like the steering wheel, brake and accelerator metaphor) and simply adds functions and refinements, cross platform codecs and media center capabilities over time. Save the kitschy stylistics are for interior decorators.
Does this contravene the GNU imperative? The MINT fork a better choice? Perhaps I should start over and try MINT. Anyway my fervent hope is that talented skilled Linux coders see the above disenfranchised XP user base as an opportunity for market share insofar as that concept applies to Free Linux.