I have been using both for about six months now and have very mixed feelings.

Speed

Mozy Backup is at a lot faster pace then Carbonite. It takes full advantage of my 2MB upload speed where as Carbonite creeps along at a measly 200kb to 500 kb .This is confirmed from my readings of upload speed using NETSTATLIVE. That is really unacceptable why limit my upload to your servers once I have finished uploading to your service a file I am no longer putting any load on your server, if you let us upload at the fastest our connection can handle then we are done sooner and everyone is happy.

File Selection

MOZY lets me check a folder I want and then going forward  I know everything in that folder and subsequent folders will be backed up, Carbonite however wont always add the subsequent folders you put inside of the ones you already said YES to. It may do some files but it  cant seem to  learn that I always want all of my videos backed in my folder that has my camera pics that sometimes i take short videos and they come in to the same folder. All I want is not to have to dig four or five folders deep just to find out that i forgot to right click and say back up videos in this folder. PLEASE o Please Carbonite give a list that we can check off the types of files we want that you seem to in your great wisdom think we dont want to back up…… and then there is the file name restrictions it wont back up files with the Tilda ~ in  the name and a large list of other files i found this list at http://www.tomkirkham.com/node/109 the files excluded are

The following file types are excluded from Carbonite backups:

.bak;.log;.cab;.cf1;.chm;.com;.cpl;.dll;.dmp;.drv;.evt;.exe;.inf;.ico;.iso;.jar;.lex;.lib;.msi;.msm;
.mst;.ocx;.otf;.pnf;.pf;.prn;.reg;.rll;.swf;.sys;.ttf;.tmp;.vxd;.chq;.chw;.hlp;.hxi;.hxq;
.hxr;.hxs;.abf;.afm;.bdf;.dfont;.eot;.fnt;.fon;.lwfn;.otf;.pfa;.pfb;.pfm;.suit;.ttc;.ttf;.ani;.ann;
.bmk;.cnt;.cpl;.cur;.dev;.drv;.dvd;.ffa;.ffl;.ffo;.ffx;.ftg;.fts;.gid;.grp;.idx;.img;
.ini;.ins;.ipf;.isp;.its;.kbd;.kext;.key;.msc;.msp;.nt;.plist;.pol;.pref;.prf;.pwl;.reg;
.scf;.scr;.sdb;.swp;.sys;.theme;.vga;.vgd;.vxd;.fxp;.jse;.obs;.prg;.rox;.shb;
.tms;.vbe;.wpk;.$$$;.$db;.113;.abk;.bac;.bck;.bcm;.bdb;.bkf;.bkp;.old;.rdb;
.win;.PCH;.SBR;.PDB;.OBJ;.BSC;.ILK;.NCB;.IDB;.v2i;.ost;.lnk;.vhd;.vmc;.vmdk;.vmsd;.vmx;.vmsn;

system/;dtSearch*;Intermediate *;VMWare*;Virtual PC*;Virtual Machine*

Additionally, music and video files are excluded during free trial subscriptions of Carbonite.

Files that end in “_” or “~” don’t get “Back this up” option in context menu. It means it’s a compressed system file. It can be renamed (from the command line) to an extension w/out the “_” (underscore)or the “~”(tilde) and then you will get the backup option.”

Excuse me for wanting to select the folder i wish to back up and not have to worry if i have videos or particular named files in it. Give me control.
Carbonite will let you tell it to back up particular files by right clicking and say back up this file type in all folder, thats nice but its only half way there because even if you right click a video file and say back up videos in this folder it still only applys to just that folder and not GLOBALLY to all video files and if that video file has a ~ or a – in the name in the wrong place then your out of luck.

Interface

Carbonite gets this catagory from me partially. I love the dots ,the green dots make me happy. Carbonite overlays green dots on the icons of files it has backed up . It also gives you partial dots on folder part way backed up. what i wish it did do that it does not, if the folder it has backed up has any folders that are empty it gives you a reading of only partially backed up.why not just ignore empty folders and give me a green dot . That empty folder could be ten levels deep and you still only get partial backed up dot. I DO LOVE THE dots but they could be improved.

Mozy on the other hand doesnt let you know if it has backed a particular file. so for me this isnt a huge deal when i know that any folder mozy is monitoring will be backed up regardless.But for this catagory the win goes to Carbonite.

Interface Speed

Mozy does seem to think alot more than carbonite this could be the fact that mozy is not intergrated into the windows interface the same as carbnonite.It is especially noticable when pulling up the configure button on mozy.

STILL NOT DONE but thats what i have so far to say.

I had a comment from spideroak and unfortunatly the priceing puts them out of my thought process all together
Spideroak Price: $10 per month Incremental: Add 100 GBs for $10 per month

sorry but thats close to just buying a spare harddrive every 10 months compared to UNLIMITED with both mozy and Carbonite for  3-5 dollars per month depending on your coupon code.

I currently am backing up about 280 gbs to both carbonite and mozy so if i were to use spideroak that would be $30 a month sorry but again thats not practical. no matter how good the software.

thats equal to amazons s3 service for the amount of data i wish to backup and my size is only going to grow as i add about 1000-2000 photos a year.

Again not done yet will add as i think of it.