Before I offer my 2 cents, let's go a little farther with the quotes:

Matthew 4:1-3, 11
Then Jesus was led up by the Spirit into the wilderness to be tempted by the devil.
2 And after He had fasted forty days and forty nights, He then became hungry.
3 And the tempter came and said to Him, "If You are the Son of God, command that these stones become bread." ...
11 Then the devil left Him; and behold, angels came and began to minister to Him. (NASU)

Luke 4:1-3, 13
Jesus, full of the Holy Spirit, returned from the Jordan and was led around by the Spirit in the wilderness
2 for forty days, being tempted by the devil. And He ate nothing during those days, and when they had ended, He became hungry.
3 And the devil said to Him, "If You are the Son of God, tell this stone to become bread." ...
13 When the devil had finished every temptation, he left Him until an opportune time. (NASU)

Mark 1:12-13
12 Immediately the Spirit impelled Him to go out into the wilderness.
13 And He was in the wilderness forty days being tempted by Satan; and He was with the wild beasts, and the angels were ministering to Him. (NASU)

: The question is: Does Mark give different detail than Matthew. Did angels attend to Jesus (I don't mean feed him) during the 40 days? This portion of Mark is clearly a summary, so it may have been Mark's way of writing the same information, but it also may be different information. There many times when the detail from gospel to gospel is different. I just wonder if this is one of them.

The three accounts each give some different details, although I had not thought the attendance of the angels was one of them. Mark's particular details that are not really stated by the other two writers include the idea of immediacy, plus the strength of the Spirit's urge to go into the wilderness, and the bit about the wild animals. Matthew puts an emphasis on the purpose, that he went into the wilderness to be tempted by Satan, that this was a purposeful testing, and not just a happenstance. Luke puts a heavy emphasis on the guidance of the Holy Spirit, before, during and after the wilderness experience (including the following verse in Luke, not quoted above).

: Is it possible that Marks is telling us that the angeles protected Jesus from harm during his time in the wilderness? And also attended him after the devil had tempted him. Even Satan notes the potential for the angel's assistance in the second temptation.

Mark's mention of the wild beasts is intriguing. Perhaps it is intended to be related to the attendance of angels, as in the story of Daniel in the lions' den (Daniel 6), or then again perhaps it was connected to the prophetic idea of the lion and the lamb and the bear and the ox together (Isaiah 11:6-7). I would be inclined to think that Mark's mention of the ministration of the angels parallels Matthew's, that he is just briefly mentioning or summarizing important factors, and that the angelic attendance was apparent in the aftermath rather than during the ordeal. The word for "attended" or "ministered" is the same one we have in reference to service in Mark 1:31 and 15:41 (and several other New Testament passages). Having said that, however, and looking over your question and various alternatives, I must note that the Psalm quoted by Satan in Matthew 4:6 specifically mentions safety from wild animals... and that is Mark's most likely reference point, and might suggest the angelic guardianship was ongoing during the 40 days, whether visible or not, though they did not keep Satan from him, and probably were more palpably present at the end.

Ps 91:11-13
11 For He will give His angels charge concerning you,
To guard you in all your ways.
12 They will bear you up in their hands,
That you do not strike your foot against a stone.
13 You will tread upon the lion and cobra,
The young lion and the serpent you will trample down.
NASU

One curiousity is that most people don't really think in terms of the 40 days of temptation, which all three writers mention, but just focus on the three tests highlighted by Matthew and Luke as though that was the whole story. The three are chosen for a reason, but clearly not the entire scope of the testing.

: The one conclusion that I have reached is that we too often jump to conclusions by reading the "preferred" gospel account and too often don't consider that the detail might get in the way of the real point of why God inspired the writer to write a certain way.

Seems like I've been recommending a lot of books lately, but here I go again. Men With A Message by John Stott is a pretty good treatment of the different perspectives the New Testament writers bring to their topics, and some of the apparent reasons for the information they include. It's the kind of analysis I enjoy. There's a bit of a review elsewhere on Living Waters