The guy was kidding, right?
Sony A57 -
horrible moire problem (see the roofs in
this video, esp. at 1:15)
Sony NEX-3 -
the usual NEX moire challenges, no standard mic input and no viewfinder
Panasonic DMC-G3 - no 1080/60p and no mic input (the G5 has 1080/60p, but no mic input)
Panasonic DMC-GX1 - no viewfinder, no mic input
If you're going to get a Panasonic DSLM, at least get one with a viewfinder and a mic input.
So far, that is the GH1, G2, GH2, GH3 and the upcoming G6.
Your friend on the other forum is correct in one respect, however. DSLRs are not optimized for video. The primary evidence for this is that their reflex mirrors (the "R" in DSLR) block their viewfinders in video or "live view" mode. DSLR shooters put up with this because these cameras produce such great video images, but I personally refuse to deal with it.
Many of the Sony DSLT ("T" is for their translucent mirror) and Panasonic DSLM ("mirrorless") models recommended above have electronic viewfinders that are not blocked and continue to work while shooting video.
This was part of the reason I switched from Canon DSLRs to Panasonic DSLMs The other reasons were Canon's moire problem, the lack of video autofocus in early Canon Rebel DSLRs, and their 12 minute continuous video clip length limit.
The new Nikons, however, have at least addressed the moire problem - and, along with the latest Canons (650D and 700D), have video autofocus capability. The new DSLRs also increase the continuous video clip length limit to 30 minutes - still short of Panasonic's 2 hour plus limit, but better.
At your price point, I would try to stretch my budget and get the moire resistant Nikon D5200 - but, if you cant, that $469 600D will meet your needs. At least it has a mic input and articulated LCD.
But be very careful of patterned subjects such as rooftops, brickwork and patterned fabrics. Moire can cause you real problems, as in these Canon 60D/Panasonic GH2 comparison videos:
http://vimeo.com/20565849
http://vimeo.com/21962491
If moire is a concern for you, here is a body-only GH2 at auction,
currently at $350 on eBay AU (only 1 hour left as of this posting)
Here is another, with the 14-42 kit lens,
up for bid at $650, with 2 days left.
Again, hope this is helpful.
Bill