I've commented on this list of ideas and supports which facilitated our trip and, in essence, made our lives much easier.

• Guides: Accurate, up-front information and research online is essential to a trip like this for me! Once again, Santa Claus brought us three pocket sized Frommer's guides (Rome/Florence/Venice) which served us well when navigating such vast attractions and city transit. We also used audio guides in several buildings, including the maze that is the Vatican Museum, which were very helpful.
• Passes: In Rome we used the RomaPass (1 each) which enabled 3 day unlimited use of public transport for above and below ground. It also gave us free access to two museums (from a list), quick lines, and a discounted price at others. It was very good value for our busy trip and easy to use.
• Money: Check with your card company before leaving so they know the card may be used abroad. Nothing worse than spending valuable travel time sorting out banking issues. Further, order foreign cash at your bank before you depart, as last minute attempts to purchase currency risk amounts not being available. We secured, through our choice of traveler's credit card, medical insurance while abroad and felt very safe.
• Packing: We traveled in an incredibly light manner. Small knapsack each. Although space was limited, our ability to move around the city (and especially through airports and customs) was greatly improved. Had we desired, we could have mailed anything beyond capacity home ahead of us. Further, don't screw with the airlines... make sure you're following the latest security procedures!!! A comfortable, tried pair of shoes is essential (we literally walked miles in some of the attractions in Rome, Florence and Venice).
• Booking Accommodations: We booked everything online, well in advance. We looked for several specific things; A/ Reasonable price, B/ proximity to railway station, major transportation links, and attractions, C/ an included breakfast, and D/ free wireless. Knowing what you are looking for helps as the choices in this tourist rich market are endless.
• Organization: Create for yourself a log book to warehouse your important travel documents. My book had an itinerary, budget, checklist, attraction and ticket confirmation numbers, copy of passports, reservations, specific maps as well as on site information to support visits (ie: Items we wanted to see). For example, for train ticket purchase Jane handed over the ticket request sheet from our log. No miscommunication possible and the tickets were perfect. It looked and felt very organized.
• Communication: This year Santa brought a family I-pod Touch for Christmas. Through Skype and wireless connections (we tried to include free wireless in our hotel choices) we had great contact home via I-pod - computer... plus e-mail. And yes... it was all free!!! Further, the i-pod was a storage space for copies of important documents (should the worst occur) and I used it daily and during travel to make the notes I used to inform this website.
• Food and Eating: Our budget required that we use funds wisely for Italian dining. Accommodations covered all our breakfast requirements. Each evening we would "forage", which for us was a trip to the local grocer/market to pick up bread, cheese, meats, fruits, veggies and of course, water and wine (We stuck to bottled water and had no "compatibility" issues)! We packed a sandwich or two each day for the journey. We didn't starve, by any stretch of the imagination, and stopped regularly for a street side coffee, gelato, or panino when necessary. We also took in a pre- St Paddy's Day Irish pub and an excellent evening meal after viewing DaVinci's Last Supper!!!
• Transportation: Having a handle on transport is essential when visiting four cities, in a foreign country, over 9 days!!! We closely followed airline websites, had an accurate schedule for train travel, prepared information for subways and examined vaporetta routes and costs. It went without a hitch... but could have proved chaotic with the tight schedule of our itinerary had we not been prepared.