I recently purchased the HDR-7500T and have almost comes to grips with it. It is working fine, and my only gripes are the poor ergonomics of the remote control and the lack of built-in editing facilities for recordings. Because there seems to have been a lot of discussion about editing I thought that I would offer my experiences.
Firstly, I have the latest firmware update, and my computer is a Mac running OS X 10.7. I have not encountered encountered any problems in uploading recorded programs to the computer by either USB drive or an external HD (Seagate). The recordings are primarily sporing events that I want to edit down to the highlights and then burn to DVD for archiving. Coincidentally, the recent High Court decision seems to have cleared up the legality of doing this.
In the past MPEG Streamclip has been my favourite editing tool, but I found that is not interested in the encrypted Humax .ts format. I found two alternatives - File Converter in Roxio Toast Titanium 9, and Aunsoft Video Converter. Toast also has an editing facility, but I couldn't get it to work (this is an Elgato product which has been replaced in Toast 10), but it at least gave me an MP4 file which I could then edit in Streamclip. Aunsoft (free to try, but it leaves a watermark) has a good selection of HD formats for conversion, and it allows simultaneous cropping of unwanted lead-in and lead-out padding. In Streamclip I was then able to cut out other unwanted content.
Fortunately I have kept my old Panasonic RAM disc recorder, and by connecting the Humax to this via component cable I can also copy the recordings from the Humax direct to DVD and do basic editing as well. The quality is not the same, but still quite acceptable.
Finally I use iSedora as the DLNA server on the Mac for streaming back to the TV or PVR. It works well.