When searching for the easiest way to level up in modern warfare 2, I first stumbled upon Yahoo Answers. That's where a guy was asking for the fastest way to level up in modern warfare 2, and was given the following answer:

"My personal experience is that I am a run and gunner so I have been leveling up crazy fast playing CTF. Every time you touch the flag 50 XP, return the flag 50XP, kill someone 50XP and capture the flag 250XP! So I usually AVERAGE around 2K-4K every game." Dwayne. "What is the fastest way to level up on Modern Warfare 2?." 2010. Yahoo! Inc. 02 September 2010 <http://answers.yahoo.com/question/index?qid=20091117151814AApRDLn>.

And then eHow of all places had a pretty good writeup about how to level up fast in the modern warfare 2 game in multiplayer mode. One gem from that writeup involves the following advice:

"Select team death match and put your kill limit on maximum, and time on unlimited. Also to make things faster i recommend putting no respawn delay and turn kill cam off." Randyk. "How to Level up fast in modern warfare 2 multiplayer." 2010. 02 September 2010 <http://www.ehow.com/how_5639397_level-fast-modern-warfare-multiplayer.html>.

The Digital Warfare 24/7 forum also offers a variety of opinions on what is the fastest or easiest way to level up in modern warfare 2. Here is a sample:

"do ground war, 250 kills with each gundo as many challenges as you canpro all the perksuse all the equipment" Brigstock, Matthew. "What Is The Fastest Way To Level-Up?." 2010. Digital Warfare 24/7 Forums. 02 September 2010 <http://forums.digitalwarfare247.com/index.php?/topic/9656-what-is-the-fastest-way-to-level-up/>.