My feedback on Mint 11 LXDE RC follows...
For the record, I have the LXDE RC installed on an 8GB bootable USB stick created using Unetbootin, and I checked the MD5 to ensure the ISO was AOK - golly, the TLA's (Three-letter acronyms) are out in force today!
1) First impressions: looks great. Slick, quick, and minimalist, yet retaining the Minty goodness. I'm impressed.
2) Wireless on my Dell Inspiron Mini 10 netbook, booting from the above USB stick, worked fine out of the box. No such luck with wireless broadband via my USB wireless dongle (Virgin Mobile is the ISP, and the device is a Huawei E160E USB stick). In this regard, seems similar to recent issues I've had with LMDE.
3) It seems there's no app included to take advantage of my built-in webcam (Cheese, etc), and I haven't downloaded an app to test this. I suggest that including one would be a fine idea.
4) The changes to the installer are welcome - it seems more simple and intuitive than ever, and I especially like the "detect keyboard" function! Nice touch.
5) That said, it wasn't easy as easy as I'd have liked to partition my USB stick within the install process. I used Gparted within the LiveCD/LiveUSB environment to do this, but it didn't turn out as planned, and curiously, Gparted disappeared from the system menu after I'd installed the system to the USB. For the record, I've successfully used Gparted before, and my intention this time was to allow 3GB for sdX1 as root, 128MB as swap, and the remainder of the 8GB stick as /home. Unfortunately, after creating a new partition table for the device during the install process, and creating the first partition (sdX1), there seemed no option through the GUI to create subsequent partitions for swap and /home. I did this successfully through Gparted outside of the install process, but even then, when I then went through the install process, Ubiquity didn't show sdX2 and sdX3, so I couldn't allocate them as I'd planned, and the installer put my /home on sdX1.
6) I disagree with the assertion that a completely black login process looks good. I'd read the release notes, so knew to expect it, but the uninitiated could be forgiven for thinking that the system has hung during boot.
7) The "system profiler and benchmark" is a great idea, and nicely implemented. On one occasion, I had selected a test, and it seemed to crash the profiler, causing it to quit and returned me to the desktop without a message or notification. I haven't been able to replicate this situation again (yet). Also, on a couple of occasions, I had pressed the button to select a test, and after waiting a while (>1minute), discovered that it hadn't actually conducted the test. Upon pressing the button again, it eventually did. The results could be made a little clearer - the comment at the bottom says that "a lower number is better", but curiously, a lower number results in a bigger column on the graph! This seems to be counterintuitive to me. To clarify this, the results could be ranked in order of speed, with the quickest at the top, and the comment at the bottom of the screen could be worded as such.
So, there's my $0.02 for the time being - I hope this helps! It's such a well-polished distro, and I'd like to congratulate all involved.
*EDIT* re: USB wireless dongle, I've just connected to a wireless hotspot, accessed the terminal as root, and did an "apt-get wvdial" as suggested in other posts. This downloaded a handful of files, but I still could not access wireless broadband via the system tray. The USB wireless dongle shows in the list, but when I click on it I get no spinning balls to suggest an attempted connection, nothing.