Basically, the new Mac Mini 2011 (core i5, 4gb ram, Radeon 6630) is a "real Mac", suitable for almost every purpose (not only SOHO).
I had nothing to complain about (even working with big libraries of Aperture), except for the hard disk (a 5400 rpm model), really too slow. In my normal use (I frequently must open/close several programs), I worked better with my iMac late 2009 (a 3,06 Core2 Duo, 4gb ram, which has a geek bench score of 4200, vs the 6900 of the MacMini!) mainly because of the 7200 rpm hd
I changed the original hd with a new ssd sata 3 (by OCZ) and installed 8gb ram (before was only 4).
I really had no problems in doing that. Thanks to the iFixit tools, in about 40 min completed my job
Thanks to the guides provided by iFixit, I think that this job is in everybody's reach.
You spend almost 200 bucks (for the ssd and the memory upgrade), but with a huge improvement in performance (the booting time is astonishing, the programs open instantly, and so on)