I first bought a Galaxy Tab 7″ Wifi Only from Fry’s Electronics, but afterwards I found out that not only did Samsung remove the HDMI port, but also put in an older, slower processor in it to save on cost. The 7″ GT got great reviews, but that was the 3G version and not the Wifi Only version, so I returned it and got a refund (lost 15% restocking fee).
I then searched on Craigslist and bought the Sprint 7″ GT, and it also included an extra charging cable and car adapter, a silicone case, and a leather case so I think I still came out ahead. It was running Froyo as seen below. To check which version of Android you are running, pick Menu > Settings > About My Galaxy Tab and this is what I have:

Pvtjoker42 on the XDA forum posted the link to update Froyo to Gingerbread (post #238):
http://forum.xda-developers.com/showthread.php?t=1148447&page=14
I renamed update_from_EB28_to_EF17.zip file to update.zip then copied and pasted it to the root of the micro sdcard and tried to update the GT using the following procedure:
To boot your Galaxy Tab into the recovery mode do the following:
Press and hold the Home + Volume Up keys
Press the Power key until you see the Samsung logo then release all the keys.
You then should see this:

As shown in the pic above, use the volume buttons down until you pick the update.zip, then hit the home key. I got the following icon:

It didn’t work, I got the following error:

I tried again, but nothing, then Meggyver in post #241 stated that he formatted a spare sdcard and put the update.zip on there and it worked. The 16 Gb micro sdcard in the GT had about 14Gb worth of stuff on it, so I put the update.zip on an empty 8Gb micro sdcard I had. I didn’t format it though because I didn’t know if it was supposed to be formatted to NTFS or fat32. It didn’t matter because this time I got the unpacking icon!

A few minutes later, I was rocking Gingerbread EF17 Android 2.3.4:

TLDR:
1: Put update.zip onto root of micro sdcard
2: Boot into recovery
3: Apply update.zip
4: If that doesn’t work, put update zip on an empty micro sdcard and go to step 1.