Those aren't real issues. The mem card slots won't be missed. 2 usb ports are sufficient. If you need more, hub it out.
B/C is NOT a major issue unless you have a shit load of ps2 games, and no ps2 to play them on. If you want to consolidate your consoles, by all means get the 80gb.
Where is the problem? The 40gb does the main two things people want from the console...ps3 games and Blu-Ray movies.
If they gave people NO option on console features and completely removed B/C...then we'd have a MAJOR issue.
BTW, how many times have you used your media card slots or used more than 2 usb ports?